The On-Line Encyclopedia of Integer Sequences

  title={The On-Line Encyclopedia of Integer Sequences},
  author={N. J. A. Sloane},
  journal={Electron. J. Comb.},
  • N. Sloane
  • Published 24 December 2003
  • Computer Science
  • Electron. J. Comb.
The On-Line Encyclopedia of Integer Sequences (or OEIS) is a database of some 130000 number sequences. It is freely available on the Web ( and is widely used. There are several ways in which it benefits research: 1 It serves as a dictionary, to tell the user what is known about a particular sequence. There are hundreds of papers which thank the OEIS for assistance in this way. 1 The associated Sequence Fans mailing list is a worldwide network… 
Sloane's Gap. Do Mathematical and Social Factors Explain the Distribution of Numbers in the OEIS ?
The Online Encyclopedia of Integer Sequences (OEIS) is a catalog of integer sequences. We are particularly interested in the number of occurrences of N(n) of an integer n in the database. This number
The encyclopedia of integer sequences
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Any word of length n has a non-empty set of periods, which is a subset of [0, n − 1], which can be denoted as a set, but also as a binary vector oflength n indexed from 0 until n −1 in which an entry equals 1 if an integer is a period of the word and 0 otherwise.
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Finding a sequence of transpositions that transforms a given permutation into the identity permutation and is of the shortest possible length is an important problem in bioinformatics. Here, a
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When my "Handbook of Integer Sequences" came out in 1973, Philip Morrison gave it an enthusiastic review in the Scientific American and Martin Gardner was kind enough to say in his Mathematical Games


The encyclopedia of integer sequences
This book presents methods for Computer Investigation of Sequences, a method for hand analysis of sequences, and some of the methods used in this work, as well as suggestions for further study.
Some canonical sequences of integers
Arithmetical properties of permutations of integers
For the finite case let a1 , a 2 , . . ., an be a permutation of the integers 1, 2, . . ., n and for the infinite case let a 1 , a2 , . . ., ai , . . . be a permutation of all positive integers .
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  • 1980
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