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A118301
Number of partitions of n into distinct parts with largest part congruent to n modulo 2.
5
1, 1, 1, 1, 2, 2, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16, 19, 23, 27, 32, 38, 44, 52, 61, 71, 83, 96, 111, 128, 148, 170, 195, 224, 256, 293, 334, 380, 432, 491, 557, 630, 713, 805, 908, 1024, 1152, 1295, 1455, 1632, 1829, 2049, 2291, 2560, 2859, 3189, 3554, 3958, 4404
OFFSET
1,5
COMMENTS
a(2*n) = A026838(2*n), a(2*n-1) = A026837(2*n-1);
a(n) = A000009(n) - A118302(n);
a(A090864(n)) = A118303(n)/2 = A000009(A090864(n))/2.
FORMULA
Conjectural g.f.: A(x) = Limit_{N -> oo} ( Sum_{n = 0..2*N+1} (-1)^(n+1)/Product_{k = 1..n} 1 - x^(2*k-1) ). - Peter Bala, Feb 11 2021
EXAMPLE
a(11) = #{11,9+2,7+4,7+3+1,5+4+2,5+3+2+1} = 6;
a(12) = #{12,10+2,8+4,8+3+1,6+5+1,6+4+2,6+3+2+1} = 7.
CROSSREFS
Sequence in context: A094983 A238218 A015744 * A018121 A256636 A258327
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Apr 22 2006
STATUS
approved