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A147900 Number of permutations of floor(i*3/2), i=0..n-1, with all sums of 2 through 4 adjacent terms respectively unique. 0
1, 2, 6, 16, 74, 368, 1776, 9208, 53466, 314212, 2134376, 14852630, 117199526, 945570742, 8407963796, 76231574308 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..16.

CROSSREFS

Sequence in context: A147886 A147924 A147908 * A147892 A147909 A147911

Adjacent sequences:  A147897 A147898 A147899 * A147901 A147902 A147903

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 17 2008

STATUS

approved

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Last modified December 5 04:10 EST 2021. Contains 349530 sequences. (Running on oeis4.)