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A178020
Number of permutations of 3 copies of 1..n with no element e[i>=2]<e[1+floor((i-2)/5)] (5-way heap).
0
1, 10, 200, 13440, 2097900, 442030200, 257134170000, 122150707608000, 111415794466080000, 163780469919918720000
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
Table of n, a(n) for n=1..10.
CROSSREFS
Simple 2-way heap A056971.
Sequence in context: A051262 A367201 A362723 * A279833 A041183 A210168
Adjacent sequences: A178017 A178018 A178019 * A178021 A178022 A178023
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 17 2010
STATUS
approved

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Last modified October 21 00:05 EDT 2024. Contains 376963 sequences.
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