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A320607
Number of parts in all partitions of n in which no part occurs more than four times.
3
1, 3, 6, 12, 15, 29, 41, 65, 91, 132, 179, 257, 339, 465, 616, 823, 1062, 1402, 1790, 2320, 2939, 3750, 4701, 5946, 7398, 9243, 11428, 14161, 17368, 21372, 26056, 31823, 38596, 46838, 56499, 68208, 81868, 98292, 117489, 140390, 167068, 198796, 235655, 279239
OFFSET
1,2
LINKS
FORMULA
a(n) ~ 3^(1/4) * log(5) * exp(2*Pi*sqrt(2*n/15)) / (2^(5/4) * 5^(1/4) * Pi * n^(1/4)). - Vaclav Kotesovec, Oct 18 2018
MAPLE
b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(2*i*(i+1)<n, 0, add(
(l-> [0, l[1]*j]+l)(b(n-i*j, min(n-i*j, i-1))), j=0..min(n/i, 4))))
end:
a:= n-> b(n$2)[2]:
seq(a(n), n=1..50);
MATHEMATICA
Table[Length[Flatten[Select[IntegerPartitions[n], Max[Tally[#][[All, 2]]]<5&]]], {n, 50}] (* Harvey P. Dale, May 18 2020 *)
CROSSREFS
Column k=4 of A210485.
Cf. A035959.
Sequence in context: A290258 A277335 A267353 * A281063 A032602 A116593
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Oct 17 2018
STATUS
approved