A151591 Number of permutations of 3 indistinguishable copies of 1..n arranged in a circle with exactly 3 adjacent element pairs in decreasing order.

0, 2, 732, 22360, 386375, 5339202, 66391738, 781132256

Offset

1,2

Links

Table of n, a(n) for n=1..8.

Crossrefs

Sequence in context: A072384 A109949 A375956 * A252986 A247080 A145124

Adjacent sequences: A151588 A151589 A151590 * A151592 A151593 A151594

Keyword

nonn

Author

R. H. Hardin, May 21 2009

Status

approved