A147942 Number of permutations of floor(i*9/7), i=0..n-1, with all sums of 2 through 4 adjacent terms respectively unique.

1, 2, 6, 16, 74, 304, 1424, 7946, 39908, 231442, 1351720, 9447558, 67300148, 488187450, 4266438488, 36066619444

Offset

1,2

Links

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

Crossrefs

Sequence in context: A147902 A147893 A147951 * A147933 A147886 A147924

Adjacent sequences: A147939 A147940 A147941 * A147943 A147944 A147945

Keyword

nonn

Author

R. H. Hardin, Nov 17 2008

Status

approved