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A245666
Number of permutations of length n with longest increasing subsequence of length 10.
2
1, 100, 5941, 275705, 11110464, 410474625, 14353045401, 484748595081, 16029615164446, 523952747921310, 17044414451764396, 554568496974014588, 18113988555378974988, 595604303387826752023, 19755504320385394380715, 662039152774864970449891
OFFSET
10,2
LINKS
MAPLE
h:= proc(l) local n; n:= nops(l); add(i, i=l)! /mul(mul(1+l[i]-j
+add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n) end:
g:= (n, i, l)-> `if`(n=0 or i=1, h([l[], 1$n])^2, `if`(i<1, 0,
add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
a:= n-> g(n-10, min(n-10, 10), [10]):
seq(a(n), n=10..30);
CROSSREFS
Column k=10 of A047874.
Sequence in context: A204081 A053109 A151647 * A210814 A065689 A260859
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 28 2014
STATUS
approved