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A212546
Number of partitions of n containing at least one part m-6 if m is the largest part.
2
0, 0, 1, 1, 3, 4, 8, 11, 19, 26, 40, 54, 79, 104, 146, 190, 257, 330, 436, 552, 715, 896, 1140, 1415, 1777, 2184, 2711, 3308, 4063, 4922, 5995, 7214, 8720, 10435, 12525, 14910, 17793, 21076, 25016, 29507, 34850, 40941, 48148, 56351, 66007, 76995, 89855, 104484
OFFSET
6,5
LINKS
FORMULA
G.f.: Sum_{i>0} x^(2*i+6) / Product_{j=1..6+i} (1-x^j).
EXAMPLE
a(8) = 1: [7,1].
a(9) = 1: [7,1,1].
a(10) = 3: [7,1,1,1], [7,2,1], [8,2].
a(11) = 4: [7,1,1,1,1], [7,2,1,1], [7,3,1], [8,2,1].
a(12) = 8: [7,1,1,1,1,1], [7,2,1,1,1], [7,2,2,1], [7,3,1,1], [7,4,1], [8,2,1,1], [8,2,2], [9,3].
MAPLE
b:= proc(n, i) option remember;
`if`(n=0 or i=1, 1, b(n, i-1)+`if`(i>n, 0, b(n-i, i)))
end:
a:= n-> add(b(n-2*m-6, min(n-2*m-6, m+6)), m=1..(n-6)/2):
seq(a(n), n=6..60);
MATHEMATICA
b[n_, i_] := b[n, i] = If[n == 0 || i == 1, 1, b[n, i - 1] + If[i > n, 0, b[n - i, i]]];
a[n_] := Sum[b[n - 2 m - 6, Min[n - 2 m - 6, m + 6]], {m, 1, (n - 6)/2}];
a /@ Range[6, 60] (* Jean-François Alcover, Dec 07 2020, after Alois P. Heinz *)
CROSSREFS
Column k=6 of A212551.
Sequence in context: A212545 A357878 A358910 * A212547 A212548 A212549
KEYWORD
nonn
AUTHOR
Alois P. Heinz, May 20 2012
STATUS
approved