Home Mathematics Some new van der Waerden numbers and some van der Waerden-type numbers
Article
Licensed
Unlicensed Requires Authentication

Some new van der Waerden numbers and some van der Waerden-type numbers

Published/Copyright: May 7, 2009
Become an author with De Gruyter Brill
Integers
From the journal Volume 9 Issue 1

Abstract

The van der Waerden number w(r; k1, k2, . . . , kr) is the least m such that given any partition {1, 2, . . . , m} = P1P2 ∪ ⋯ ∪ Pr, there is an index j ∈ {1, 2, . . . , r} such that Pj contains an arithmetic progression of length kj. We have computed exact values of some (30) previously unknown van der Waerden numbers and also computed lower bounds of others. Let wd(r; k1, k2, . . . , kr) be the least m such that given any partition {1, 2, . . . , m} = P1P2 ∪ ⋯ ∪ Pr, there is an index j ∈ {1, 2, . . . , r – 1} such that Pj contains an arithmetic progression of length kj, or Pr contains an arithmetic progression of length kr with common difference at most d. A table of observed values of wd(r; k1, k2, . . . , kr) for d = 1, 2, . . . , is given.

Received: 2008-11-15
Accepted: 2009-02-21
Published Online: 2009-05-07
Published in Print: 2009-April

© de Gruyter 2009

Downloaded on 1.4.2026 from https://www.degruyterbrill.com/document/doi/10.1515/INTEG.2009.007/html
Scroll to top button