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 A007783 Mixed Van der Waerden numbers w(n, 3; 2). 3
 3, 6, 9, 18, 22, 32, 46, 58, 77, 97, 114, 135, 160, 186, 218, 238, 279, 312, 349 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is the smallest number M such that if each integer 1, 2, ..., M is colored using one of two colors (say red and blue), then there must be an arithmetic progression of length 3 in one color (red) or an arithmetic progression of length n in the other color (blue). So the first term, w(1, 3; 2), is 3. - Donald Vestal, May 31 2005 Extended computations via SAT-solving in Ahmed, Kullmann, Snevily, 2011. REFERENCES V. Chvatal, Some unknown Van der Waerden numbers, pp. 31-33 of R. K. Guy et al., editors, Combinatorial Structures and Their Applications (Proceedings Calgary Conference Jun 1969}), Gordon and Breach, NY, 1970. Bruce M. Landman and Aaron Robertson, Ramsey Theory on the Integers, Amer. Math. Soc., 2004. LINKS T. Ahmed and O. Kullmann and H. Snevily, On the van der Waerden numbers w(2;3,t), arXiv:1102.5433 [math.CO], 2011-2014. M. D. Beeler and P. E. O'Neil, Some new Van der Waerden numbers, Discrete Math., 28 (1979), 135-146. CROSSREFS Cf. A002886 has the same definition but an incorrect first term. Sequence in context: A324283 A161338 A047847 * A050625 A025614 A182751 Adjacent sequences:  A007780 A007781 A007782 * A007784 A007785 A007786 KEYWORD nonn,hard AUTHOR Matthew Klimesh (matthew(AT)engin.umich.edu) EXTENSIONS Entry revised by N. J. A. Sloane, Jun 01 2005 a(16)-a(19) from Oliver Kullmann, Oct 28 2011 STATUS approved

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Last modified October 16 13:51 EDT 2019. Contains 328093 sequences. (Running on oeis4.)