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A092311
Total number of largest parts in all partitions of n into odd parts.
16
1, 2, 4, 5, 7, 10, 12, 14, 19, 23, 26, 33, 38, 44, 56, 63, 71, 88, 99, 114, 138, 155, 176, 208, 237, 269, 314, 357, 402, 468, 529, 594, 686, 772, 873, 999, 1119, 1260, 1431, 1608, 1804, 2039, 2284, 2554, 2884, 3219, 3590, 4032, 4493, 5011, 5603, 6231, 6928
OFFSET
1,2
LINKS
FORMULA
G.f.: Sum((x^(2*n-1)/(1-x^(2*n-1)))/Product((1-x^(2*k-1)), k=1..n), n=1..infinity).
a(n) ~ exp(Pi*sqrt(n/3)) / (4 * 3^(1/4) * n^(3/4)). - Vaclav Kotesovec, Jul 07 2019
EXAMPLE
Partitions of 6 into odd parts are: [1,1,1,1,1,1], [1,1,1,3], [3,3], [1,5]; thus a(6)=6+1+2+1=10.
MATHEMATICA
nmax = 50; Rest[CoefficientList[Series[Sum[(x^(2*n - 1)/(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 *)
lpp[k_]:=Module[{c=Max[k]}, Count[k, c]]; Table[Total[lpp/@Select[IntegerPartitions[ n], AllTrue[ #, OddQ]&]], {n, 60}] (* Harvey P. Dale, Apr 24 2023 *)
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Feb 16 2004
EXTENSIONS
More terms from Pab Ter (pabrlos(AT)yahoo.com), May 25 2004
STATUS
approved