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A320372 Number of parts in all partitions of n with largest multiplicity two. 2
2, 0, 5, 6, 9, 13, 23, 30, 44, 58, 85, 108, 149, 191, 258, 326, 425, 532, 688, 852, 1082, 1331, 1670, 2042, 2531, 3068, 3771, 4554, 5543, 6653, 8051, 9607, 11543, 13722, 16377, 19390, 23023, 27132, 32073, 37660, 44303, 51834, 60744, 70813, 82666, 96082, 111759 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 2..5000

FORMULA

a(n) ~ log(3) * exp(2*Pi*sqrt(n)/3) / (2*Pi*n^(1/4)). - Vaclav Kotesovec, Oct 25 2018

MAPLE

b:= proc(n, i, k) option remember; `if`(n=0, [1, 0], `if`(i<1, 0,

      add((l-> [0, l[1]*j]+l)(b(n-i*j, i-1, k)), j=0..min(n/i, k))))

    end:

a:= n-> (k-> (b(n$2, k)-b(n$2, k-1))[2])(2):

seq(a(n), n=2..60);

CROSSREFS

Column k=2 of A213177.

Sequence in context: A188724 A082832 A334842 * A097709 A197877 A104555

Adjacent sequences:  A320369 A320370 A320371 * A320373 A320374 A320375

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 11 2018

STATUS

approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)