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A243744
Number of compositions of n with exactly nine occurrences of the largest part.
2
1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 10, 55, 220, 715, 2002, 5005, 11440, 24310, 48621, 92388, 168025, 294260, 498850, 822712, 1327029, 2107325, 3324750, 5280276, 8595025, 14648920, 26637015, 52076915, 108669142, 237787000, 535084341, 1219016810, 2782344676
OFFSET
9,11
LINKS
Joerg Arndt and Alois P. Heinz, Table of n, a(n) for n = 9..650
MAPLE
b:= proc(n, p, i) option remember; `if`(n=0, p!,
`if`(i<1, 0, add(b(n-i*j, p+j, i-1)/j!, j=0..n/i)))
end:
a:= proc(n) local k; k:=9;
add(b(n-i*k, k, i-1)/k!, i=1..n/k)
end:
seq(a(n), n=9..50);
MATHEMATICA
b[n_, p_, i_] := b[n, p, i] = If[n == 0, p!, If[i<1, 0, Sum[b[n-i*j, p+j, i-1]/j!, {j, 0, n/i}]]]; a[n_] := (k=9; Sum[b[n-i*k, k, i-1]/k!, {i, 1, n/k}]); Table[a[n], {n, 9, 50}] (* Jean-François Alcover, Feb 10 2015, after Maple *)
CROSSREFS
Column k=9 of A238341.
Sequence in context: A128936 A000582 A229890 * A145459 A290893 A034241
KEYWORD
nonn
AUTHOR
Joerg Arndt and Alois P. Heinz, Jun 09 2014
STATUS
approved