Born in Bailieboro,
County Cavan, Ireland, on 5th January 1946.
Attended local school. (See BAILIEBOROUGH (A PICTORIAL PAST), by Leslie McKeague, is a wonderful tribute to my hometown of Bailieborough, County Cavan.)
1958-65. Attended various boarding schools in Ireland and England.
January 1965: awarded Open Scholarship in Mathematics to Royal Holloway College (RHC) of London University.
Undergraduate at RHC for 1965-68. Mary, my wife-to-be, was a student there
at the same time.
Summer 1968: awarded Tutorial Research Studentship at RHC for the years
1968-71, while I did my Ph.D. there.
I completed my thesis - Transcendental numbers in the p-adic domain - in 1970-71,
and was awarded a London university Ph.D. in 1972.
1971-72. Temporary lectureship in Pure Mathematics in the Mathematics department of RHC. Marie,
our first daughter, was born on June 5th, 1972.
1972-74. Temporary lectureship in Pure Mathematics in the Mathematics department of Manchester University.
October 1974 - November 1975. Temporary lectureship in Mathematics in
the Jos Campus (now the University of Jos) of Ibadan University, Nigeria.
Catherine, our younger daughter, was born in Jos on April 30th, 1975.
January 1976 - June 1988. Lectureship in Mathematics in Carysfort
College, Blackrock, County Dublin, Ireland. The College was closed - in an
act of gross vandalism - by the then Irish Government, headed G. Fitzgerald.
September 1988. Moved ("the permanent gift of the
Department of Education," according to a senior civil servant) to Mathematics
department of St. Patrick's College, Drumcondra,
Dublin 9, Ireland.
Dilcher at the July 2006 Vancouver Meeting of the Canadian Number Theory
Association, a most happy event for me, as we agreed to collaborate, and I
spent a very fruitful two weeks with Karl at Dalhousie in May 2007 (see my
colloquium talk there). As I write this, Karl is about to give a talk on
our work at the 18th
Czech and Slovak International Conference on Number Theory.
February 2007. Resigned from St Patrick's College, four
years ahead of normal retirement age. My resignation took effect from the
end of August 2007.
Now I embark on a new mathematical life, and a new life
I have a Photographs section elsewhere on my site, and I also
have many individual photos distributed in several places - some further down
this page. Here, however, in a final effort to finish work on my site before
leaving St Patrick's College, I have created a single collection of photographs
which covers the period of most of my life. Because of time I can only comment
briefly of those I include; it had been a longterm ambition to put hundreds of
photographs up on my site, but that will not now happen.
Longer biographical details
Born in the middle of a poker game at my home on Henry
Street (the second house on the left as you go
down the street from the top, just after what used to be known as 'Peetie'
Rodgers' field) in Bailieboro, County Cavan, on 5th
January 1946. My parents - Sean and Annie (née Sandes) Cosgrave - were both
primary school teachers, in three-teacher schools. My father taught me in my final three
years at primary school, in 4th, 5th and 6th classes. Dad
was a wonderful teacher, and I will only mention that he took us through a Shakespeare
play - in class - each year; in my time with him we acted through The Merchant of
Venice, Macbeth and Julius Caesar. He also taught us simultaneous
equations, the Euclidean Algorithm (though Dad wouldn't have known that it was called
that; he called it the 'ladder method') for computing the gcd of two
integers, and some Latin and French.
The grandfather of William and Henry James left Bailieboro for the 'States,'
sometime in the last century. Outside the town - in the townland of Kilinkere - was born
the well-known US Army General Phil Sheridan. He was reputed to have made the (shocking)
remark that the only good Indian was a dead one, and in recent years I heard a report on
the radio that some native Americans had visited Kilinkere in a spirit of reconciliation.
I believe that Francis Sheehy Skeffington had some connection with Bailieboro (I must
check that out...). In more recent times that little town could lay claim to the renowned
architect Patrick Shaffrey, the author Tom MacIntyre (whose mother taught me in the
'infants division'), and Captain James Kelly. The last three were all taught by my father.
In my time in Bailieboro the principal of the local Protestant primary school was Tom
Barron, a remarkable man, who donated the renowned Corleck Head to the National
Museum of Ireland (it has since been transferred to the County Cavan Museum, according to the terms of Tom's will?). That head was in Tom's school for many, many years, before he made his
gift to the museum.
In those days Bailieboro - a small
town with a population of about 1,000 - didn't have a secondary school; now it does, the
Bailieboro Community School. In September 1958 I was sent off to boarding school at
Gormanstown College, County Meath, out in the countryside between Drogheda and Balbriggan.
I didn't like Gormanstown and I ran away from it three times,
roughly after my third, fifth and sixth weeks there. After my third escape my Dad remarked
- quite perceptibly I thought - that it seemed I didn't like the school, and my parents
removed me. I spent the rest of that year back at Dad's then newly opened school, spending
most of my time reading texts on Latin and French grammar, and chopping sticks for the
In September 1959 I went to the Marist boarding school in Dundalk, Co. Louth, and I remained there for
three years. One of my friends there - Brian Donnelly - later became a colleague (first as
lecturer in, and later the head of the English Department - succeeding Seamus Heaney) in Carysfort College, Dublin.
In September 1962 I went to the Salesian boarding school in Cowley, just outside Oxford.
I spent three very agreeable years there.
In September 1965 I became an undergraduate student of Mathematics at Royal Holloway College (RHC) of London University. That
year was an historic one for RHC: it was the first year that male undergraduates were
accepted. As I won an open scholarship there, and as I was the first scholar alphabetically,
I like to claim that I was the first official male undergraduate student at RHC.
(My scholarship money enabled me to start a record collection.)
I simply loved my time at RHC, and it was there that I met
my-wife-to be, Mary (she was studying major French, with Italian as her minor subject).
We began 'going out together' on Friday 16th June 1967, just at the end of
our second year at college; we had been friends since early in our first
year. Here is a photo
of Mary and I, sometime in the summer of 1970; I think it's the earliest
photo of the two of us together.
One of Mary's fellow
students was 'Flott,' the renowned soprano Dame
Felicity Lott (who will be singing here in Dublin this November 1st,
2007 in the National Concery Hall Celebrity Series). Mary (fourth from
left) and Flott (sixth from left), and another friend Lesley, are in this
photo from Sept 1967, taken at the start of a year spent in France as
part of their degree studies. I still have letters that Mary, Flott and
Lesley wrote to me form Potiers (France), when they were there for the final
term at the end of their first year of studies. (How we in Mathematics
envied their travel as part of their degree!)
Here is an excerpt from a review of a Royal Festival Hall concert of Friday, 4th
March, 1989, marking the 60th birthday of the conductor Bernard Haitink:
"The tumultous applause which followed Bernard Haitink's spellbinding
interpretation of Mahler's Fourth Symphony with the London Philarmonic at the Royal
Festival hall on Friday evening ...
It had been a remarkably happy evening from the first, for the evening
had started with an impressive, full-hearted performance of Elgar's Introduction and
Strauss's Four last Songs followed, and here too there was in the
performance the affecting ability to range effortlessly between an intimately lyrical
expression and something more grandly mysterious and universal. Felicity Lott was a
radiant soloist and moved with grace and charm in Strauss's timeless retrospective world
Her lines flowed with a natural musicality and poetry and, together
with the subtly coloured strands of the orchestral texture, were woven into a gorgeous
tapestry by Mr Haitink.
And then there was the Mahler ...
Finally, there was an exquisite rendering of the child's view of
heaven, the orchestra tenderly rocking, Miss Lott perfectly attuned to the vision. It
formed a blissful end to a memorable evening's music-making."
Graduating in 1968 I remained at RHC for the years 1968-71 to do a Ph.D. in Number
Theory. My supervisor was John H.E. Cohn (best known for his beautiful proof of the difficult result that 144 is the
largest square Fibonacci number). In those years I held one of the College's 'tutorial
research studentships,' which meant that I was paid for giving tutorials and correcting
scripts on behalf of the head of department, the great convexity theorist, Professor H.G.
Eggleston. For the year 1969-70 I shared a house in nearby Staines with a friend Paul Goodey (who was then doing his
Ph.D. with H.G. Eggleston), and Malcolm Woolings (doing his Ph.D. with Coulter McDowall).
1971-72. Temporary lecturer in Pure Mathematics at RHC. In that year the number theorist
Roger Baker came to RHC as a lecturer, and
we became friends. Roger subsequently became a full Professor at RHC, before departing for
the USA. Mary and I married in her home town of Plymouth, Devon, on 24th. July (by chance
it was my father's 65th. birthday). Flott sang at our wedding.
1972-74. Our daughter Marie was born on June 5th, 1972.
Temporary lecturer in Pure Mathematics, Manchester
Ian MacDonald, FRS, was head there in my time. I played five-a-side soccer in a team
chosen mainly from Jeff
Paris (in goal), Nige Ray (midfield),
Mick McCrudden (general
position) and Will McLewin.
Once we defeated the Maths. dept. team from Salford university (just up the road) by 40-1,
and I scored 27 of our goals (a fact which Nige remarked upon at his 60th
birthday celebrations, which Mary and I attended in November 2005). In the year 1973-74 we were on occasion joined by visiting
Research Fellow Charles Van Loan ('Charlie').
October 1974 - November 1975.
Lecturer in Pure Mathematics at the Jos Campus of Ibadan University, Nigeria.
Our daughter Catherine Siobhan was born in Jos,
Nigeria, on 30th. April, 1975 (in later years I worried her by telling her that I had
contemplated calling her Carla Frederika, after the great Carl Frederik Gauss, whose
birthday also fell on 30th. April).
January 1976 to June 1988. Lecturer in Mathematics, Carysfort College, Dublin (where my
mother was a student for one year, away back in 1921-22). Michael Barry was a great mathematics colleague; he left Carysfort in 1987, and
since then has been in the Mathematics department of Allegheny College, Meadville, PA,
USA. We still meet from time to time, usually here in Dublin, and once - on my 49th
birthday (January 5th 1995), while attending the American Mathematical Society
winter meeting - dined out in Chinatown in San Francisco.
Following the bizzare closure of Carysfort College by the Irish government in June 1988 I transferred to
St Patrick's College (Drumcondra) in September 1988. In June 1988, a senior civil servant put it to me that I had three choices:
to emigrate, to retire (at 42!!), or to transfer to St. Partick's College.
The Mathematics departments of University College Dublin and St Patrick's
College (Maynooth) both wanted me transferred to them, and hearing from the
latter before the former I opted to go there. The then Government minister
for Education - one Mary O'Rourke - was approached by a number of TDs
(members of parliament) - Brady and O'Connell - to arrange for my transfer
to Maynooth. While initially the minister was all in favour of my going to Maynooth,
she later informed them that the Department of Finance (no less) were
insisting that I go to Drumcondra.
For the final graduation ceremony at Carysfort College in October 1988,
Seamus Heaney composed some Valedictory
Verses. (Years later, in 2002, after I had been introduced before a talk
I gave at the Southern Methodist University of Dallas, I said something
like: you know, one of the things that annoys me about Stanford folk is
that they are always going on about how many Nobel laureates they have on
their faculty; they have twelve or thirteen. Who cares? ... I once worked in
a place where about two percent of faculty (eventually) won a Nobel Prize...
(I could see them sit up!) Thing is, there were only about fifty
people working in the place anyway, and one of them was Seamus Heaney. It
got a laugh.)
In June 94 I came to know of Mathematica
(until then I was entirely ignorant of Computer Algebra Systems), and immediately realised
that I had made a gross error all those years in avoiding - like the plague - computers. I
didn't get to do anything about it until a year later when - following the advice of
Tony O'Farrell - I
investigated Maple, and that determined my future professional work.
In November 1994 - while attending a course on Chaos in St. Patrick's College,
Maynooth - I met Dr. Mark Daly. Was I impressed!! Mark Daly worked part-time hours with me
for the months Jan. 95 through to May 95, helping me get the use of Maple off the
ground in my first and second year courses. Mark worked with me for the
years 1995-98 while I was acting head of department. I
would not be able to do today, what I can do today, had it not been for him.
I continued to work in St Patrick's College until I resigned my post as head
of the mathematics department in February 2007 (four years ahead of the
normal retirement age), and I began a new life centered on my collaboration
with Karl Dilcher.
Note of February 2011. Details of recent papers that Karl and I have written available here.