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A147898 Number of permutations of floor(i*9/5), i=0..n-1, with all sums of two and three adjacent terms respectively unique. 0
1, 2, 6, 24, 96, 444, 2508, 13216, 81030, 566512, 4383340, 43168552, 356745786, 3125719866, 30567653042, 349720370632 (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: A323260 A147915 A147906 * A147890 A147912 A147903

Adjacent sequences:  A147895 A147896 A147897 * A147899 A147900 A147901

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 17 2008

STATUS

approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)