Demonstration of the
On-Line Encyclopedia of Integer Sequences® (OEIS®)
The Book Versions
Neil Sloane started collecting number sequences when he was
a graduate student
at Cornell University in the mid-1960's,
in an attempt to identify a sequence that had arisen
in the work on his dissertation.
For the full story, see his article
"My Favorite Integer Sequences", in
Sequences and their Applications (Proceedings of SETA '98),
C. Ding, T. Helleseth and H. Niederreiter (editors),
Springer-Verlag, London, 1999, pp. 103-130. Available in
The idea of a "dictionary" of integer sequences was received with enthusiasm by many
people, and in 1973 Academic Press published
A Handbook of Integer Sequences,
containing about 2400 sequences.
Over the next twenty years an enormous amount of new material arrived,
preprints, reprints, postcards, typewritten letters, handwritten letters, etc.,
and it was not until 1995 that - with Simon Plouffe's help -
the sequel appeared:
The Encyclopedia of Integer Sequences,
N. J. A. Sloane and S. Plouffe,
San Diego, 1995, 587 pp.
This contained about 5500 sequences.
The book is still useful
since it contains many of the most important sequences.
The database (which is now maybe a thousand times the size of the book)
is too huge to use except as a reference.
Additional information about the book, including links to reviews,
can be found
Some reviews will be mentioned in the
last demonstration page.
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