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A243741
Number of compositions of n with exactly six occurrences of the largest part.
2
1, 0, 0, 0, 0, 0, 1, 7, 28, 84, 210, 462, 925, 1723, 3038, 5145, 8498, 13930, 23143, 39859, 72500, 140266, 286678, 609217, 1323197, 2897511, 6339636, 13787488, 29726648, 63472185, 134190162, 280988786, 583076160, 1199816068, 2449963412, 4967798570, 10009806563
OFFSET
6,8
LINKS
Joerg Arndt and Alois P. Heinz, Table of n, a(n) for n = 6..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:=6;
add(b(n-i*k, k, i-1)/k!, i=1..n/k)
end:
seq(a(n), n=6..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=6; Sum[b[n-i*k, k, i-1]/k!, {i, 1, n/k}]); Table[a[n], {n, 6, 40}] (* Jean-François Alcover, Feb 10 2015, after Maple *)
CROSSREFS
Column k=6 of A238341.
Sequence in context: A049017 A019501 A229887 * A369809 A145456 A369808
KEYWORD
nonn
AUTHOR
Joerg Arndt and Alois P. Heinz, Jun 09 2014
STATUS
approved