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A092322
Sum of largest parts of all partitions of n into odd parts.
11
1, 1, 4, 4, 9, 12, 19, 24, 36, 48, 64, 83, 108, 140, 179, 224, 280, 352, 432, 532, 652, 795, 960, 1160, 1392, 1669, 1992, 2368, 2804, 3320, 3908, 4592, 5388, 6300, 7349, 8560, 9940, 11524, 13340, 15401, 17752, 20436, 23472, 26920, 30840, 35256, 40252, 45900
OFFSET
1,3
COMMENTS
a(n) = Sum_{k>=1} k*A116799(n,k). - Emeric Deutsch, Feb 24 2006
LINKS
FORMULA
G.f.: Sum_{n>=1} (2*n-1)*x^(2*n-1)/Product_{k=1..n} (1-x^(2*k-1)).
EXAMPLE
a(5)=9 because the partitions of 5 into odd parts are [5],[3,1,1] and [1,1,1,1,1] and the largest parts add up to 5+3+1=9.
MAPLE
g:=sum((2*n-1)*x^(2*n-1)/Product(1-x^(2*k-1), k=1..n), n=1..30): gser:=series(g, x=0, 50): seq(coeff(gser, x^n), n=1..48); # 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, 1, n}], {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