A268845 Number of sequences with n copies each of 1,2,...,9 and longest increasing subsequence of length 9.

1, 6536413529, 8167981106765263789, 5426679072605204732028894233, 2599293828638212400913690945686101111, 1025794060996626005769021866749636185341527229, 358281333933096129012031117609647623312585201668494007

Offset: 1

Author

Alois P. Heinz, Feb 14 2016

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..50
• J. D. Horton and A. Kurn, Counting sequences with complete increasing subsequences, Congressus Numerantium, 33 (1981), 75-80. MR 681905

Crossrefs

Column k=9 of A047909.

Formula

a(n) ~ 9^(9*n + 1/2) / (2*Pi*n)^4. - Vaclav Kotesovec, Mar 03 2016