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A092314
Sum of smallest parts of all partitions of n into odd parts.
11
1, 1, 4, 2, 7, 6, 11, 8, 18, 16, 24, 23, 34, 36, 51, 48, 66, 74, 90, 98, 126, 137, 164, 182, 220, 247, 294, 324, 380, 434, 496, 556, 650, 728, 835, 938, 1068, 1204, 1372, 1531, 1736, 1956, 2198, 2462, 2784, 3104, 3482, 3890, 4358, 4864, 5441, 6048, 6748, 7516
OFFSET
1,3
COMMENTS
a(n) = Sum_{k>=1} k*A116856(n,k). - Emeric Deutsch, Feb 24 2006
LINKS
FORMULA
G.f.: Sum((2*n-1)*x^(2*n-1)/Product(1-x^(2*k-1), k = n .. infinity), n = 1 .. infinity).
a(n) ~ exp(Pi*sqrt(n/3)) / (4 * 3^(1/4) * n^(3/4)). - Vaclav Kotesovec, Jul 07 2019
EXAMPLE
a(5)=7 because the partitions of 5 into odd parts are [5],[3,1,1] and [1,1,1,1,1] and the smallest parts add up to 5+1+1=7.
MAPLE
g:=sum((2*n-1)*x^(2*n-1)/Product(1-x^(2*k-1), k=n..30), n=1..30): gser:=series(g, x=0, 57): seq(coeff(gser, x^n), n=1..54); # Emeric Deutsch, Feb 24 2006
MATHEMATICA
nmax = 50; Rest[CoefficientList[Series[Sum[(2*n - 1)*x^(2*n - 1) / Product[(1 - x^(2*k - 1)), {k, n, nmax}], {n, 1, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Jul 06 2019 *)
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Feb 15 2004
EXTENSIONS
More terms from Pab Ter (pabrlos(AT)yahoo.com), May 25 2004
STATUS
approved