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A320610
Number of parts in all partitions of n in which no part occurs more than seven times.
3
1, 3, 6, 12, 20, 35, 54, 78, 119, 173, 245, 347, 480, 657, 894, 1193, 1588, 2097, 2745, 3563, 4612, 5916, 7556, 9609, 12150, 15286, 19177, 23924, 29757, 36876, 45533, 56026, 68758, 84080, 102556, 124735, 151315, 183059, 220998, 266101, 319720, 383306, 458569
OFFSET
1,2
LINKS
FORMULA
a(n) ~ 3^(5/4) * log(2) * exp(Pi*sqrt(7*n/3)/2) / (2^(3/2) * 7^(1/4) * Pi * n^(1/4)). - Vaclav Kotesovec, Oct 18 2018
MAPLE
b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(7*i*(i+1)/2<n, 0, add(
(l-> [0, l[1]*j]+l)(b(n-i*j, min(n-i*j, i-1))), j=0..min(n/i, 7))))
end:
a:= n-> b(n$2)[2]:
seq(a(n), n=1..50);
MATHEMATICA
Table[Length[Flatten[Select[IntegerPartitions[n], Max[Tally[#][[All, 2]]] <= 7 &]]], {n, 43}] (* Robert Price, Jul 31 2020 *)
CROSSREFS
Column k=7 of A210485.
Cf. A261775.
Sequence in context: A348464 A182978 A320609 * A320611 A320612 A320613
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Oct 17 2018
STATUS
approved