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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

Table of n, a(n) for n=0..11.

T. Ahmed, Some new van der Waerden numbers and some van der Waerden-type numbers, Integers, 9 (2009), A06, 65-76.

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

Cf. A217005, A217007, A217008, A217059, A217060, A217236, A217237.

Sequence in context: A303686 A185099 A216295 * A172052 A001101 A088341

Adjacent sequences:  A217055 A217056 A217057 * A217059 A217060 A217061

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 December 6 21:48 EST 2019. Contains 329809 sequences. (Running on oeis4.)