A151601 Number of permutations of 4 indistinguishable copies of 1..n arranged in a circle with exactly 6 adjacent element pairs in decreasing order.

0, 3348, 20944448, 15679525340, 5314573995408, 1226608986189748

Offset

2,2

Links

Table of n, a(n) for n=2..7.

Crossrefs

Sequence in context: A255731 A204884 A204880 * A251817 A216488 A203782

Adjacent sequences: A151598 A151599 A151600 * A151602 A151603 A151604

Keyword

nonn

Author

R. H. Hardin May 21 2009

Status

approved