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A131502 Half the number of permutations of 0..n with a zero n-th difference. 1
0, 0, 1, 1, 8, 3, 136, 29, 928, 942, 66496, 6175, 2785856, 205678, 11122048 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..14.

EXAMPLE

a(5)=3 because 0,1,2,3,4,5 ; 0,2,4,3,1,5 ; and 0,4,2,1,3,5 ; and their reverses have zero 5th differences.

CROSSREFS

Sequence in context: A038281 A302370 A303086 * A302891 A303626 A100253

Adjacent sequences:  A131499 A131500 A131501 * A131503 A131504 A131505

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 13 2007

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)