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A217058 Van der Waerden numbers w(j+2; t_0,t_1,...,t_{j-1}, 3, 4) with t_0 = t_1 = ... = t_{j-1} = 2. 7
18, 21, 25, 29, 33, 36, 40, 42, 45, 48, 52, 55 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
REFERENCES
T. C. Brown, Some new van der Waerden numbers (preliminary report), Notices American Math. Society, 21 (1974), A-432.
V. Chvatal, Some unknown van der Waerden numbers, Combinatorial Structures and their Applications (R. Guy et al., eds.), Gordon and Breach, New York, 1970.
LINKS
T. Ahmed, On computation of exact van der Waerden numbers, Integers: Electronic Journal of Combinatorial Number Theory, 11 (2011), A71.
T. Ahmed, Some more Van der Waerden numbers, J. Int. Seq. 16 (2013) 13.4.4
EXAMPLE
w(2;3,4)=18, w(3;2,3,4)=21, w(4;2,2,3,4)=25, and so on...
CROSSREFS
Sequence in context: A303686 A185099 A216295 * A172052 A001101 A088341
KEYWORD
nonn,more,hard
AUTHOR
Tanbir Ahmed, Sep 25 2012
EXTENSIONS
a(11)=55 added by Tanbir Ahmed, Dec 07 2012
STATUS
approved

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Last modified April 19 09:23 EDT 2024. Contains 371782 sequences. (Running on oeis4.)