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A178023 Number of permutations of 4 copies of 1..n with no element e[i>=2]<e[1+floor((i-2)/3)] (3-way heap) 0
1, 12, 807, 167502, 73291308, 74380051365, 168357922807266, 485556480501589584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

CROSSREFS

Simple 2-way heap A056971

Sequence in context: A341562 A155813 A220119 * A305935 A228182 A003748

Adjacent sequences:  A178020 A178021 A178022 * A178024 A178025 A178026

KEYWORD

nonn

AUTHOR

R. H. Hardin May 17 2010

STATUS

approved

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Last modified April 17 05:12 EDT 2021. Contains 343059 sequences. (Running on oeis4.)