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A027350
Number of partitions of n into distinct odd parts, the least being 3.
1
0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 2, 1, 2, 1, 3, 2, 3, 2, 4, 3, 4, 4, 5, 5, 5, 6, 7, 8, 7, 9, 9, 11, 10, 13, 13, 15, 14, 17, 18, 21, 20, 23, 25, 27, 28, 31, 34, 36, 38, 41, 46, 48, 51, 54, 61, 63, 68, 72, 80, 83, 89, 94, 104, 109, 116
OFFSET
1,19
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
G.f. sum(n>=2, x^(n^2-1)/prod(k=1,n-2,1-x^(2*k))) - Joerg Arndt, Jan 29 2011
a(n) ~ exp(Pi*sqrt(n/6)) / (2^(15/4) * 3^(1/4) * n^(3/4)). - Vaclav Kotesovec, Oct 09 2018
PROG
(PARI)
N=99; x='x+O('x^N);
t=sum(n=2, N, x^(n^2-1)/prod(k=1, n-2, 1-x^(2*k))); /* == x^3 + x^8 + x^10 + ... */
v=Vec(t) /* show terms for n>=3 */ /* Joerg Arndt, Jan 29 2011 */
CROSSREFS
Cf. A027349.
Sequence in context: A053279 A046800 A338718 * A029327 A348844 A079135
KEYWORD
nonn
STATUS
approved