The On-Line Encyclopedia of Integer Sequences (OEIS) is a comprehensive database of nearly 90,000 integer sequences, organized lexicographically. Each sequence entry includes initial terms, a description, formulas, generating programs, references, and links. The OEIS is accessible via the internet at http://www.research.att.com/~njas/sequences/ and can also be consulted via email. Users can submit sequences, and the database provides detailed information, including explicit formulas, recurrence relations, and references. The OEIS is widely used for identifying sequences, solving problems, and simplifying complex expressions. It covers a broad range of mathematical topics, including combinatorics, number theory, and recreational mathematics, and has applications in chemistry and physics. The database is maintained by a team of editors and regular contributors, ensuring accuracy and reliability. Recent examples of new sequences include the Home primes, EKG sequence, lacing a shoe, and a "bootstrap" sequence.The On-Line Encyclopedia of Integer Sequences (OEIS) is a comprehensive database of nearly 90,000 integer sequences, organized lexicographically. Each sequence entry includes initial terms, a description, formulas, generating programs, references, and links. The OEIS is accessible via the internet at http://www.research.att.com/~njas/sequences/ and can also be consulted via email. Users can submit sequences, and the database provides detailed information, including explicit formulas, recurrence relations, and references. The OEIS is widely used for identifying sequences, solving problems, and simplifying complex expressions. It covers a broad range of mathematical topics, including combinatorics, number theory, and recreational mathematics, and has applications in chemistry and physics. The database is maintained by a team of editors and regular contributors, ensuring accuracy and reliability. Recent examples of new sequences include the Home primes, EKG sequence, lacing a shoe, and a "bootstrap" sequence.