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A228621 Number of s in {1,...,n}^n having shortest run with the same value of length 2. 2
2, 0, 12, 40, 210, 840, 5208, 23760, 148410, 786720, 5137440, 30051528, 207058488, 1318599240, 9540828480, 65319695136, 495194683680, 3608366801040, 28572937581140, 219952629498840, 1813839842408748, 14663194937503288, 125593649761912704, 1061139859894326000 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 2..180

EXAMPLE

a(2) = 2: [1,1], [2,2].

a(4) = 12: [1,1,2,2], [1,1,3,3], [1,1,4,4], [2,2,1,1], [2,2,3,3], [2,2,4,4], [3,3,1,1], [3,3,2,2], [3,3,4,4], [4,4,1,1], [4,4,2,2], [4,4,3,3].

CROSSREFS

Column k=2 of A228617.

Sequence in context: A112261 A134831 A074001 * A180189 A182437 A013316

Adjacent sequences:  A228618 A228619 A228620 * A228622 A228623 A228624

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 28 2013

STATUS

approved

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Last modified June 19 05:33 EDT 2019. Contains 324218 sequences. (Running on oeis4.)