login
A117192
Number of partitions of n into distinct parts with an even rank.
10
1, 0, 2, 0, 2, 2, 3, 2, 4, 6, 6, 7, 8, 12, 14, 16, 18, 24, 26, 32, 38, 46, 52, 60, 70, 83, 96, 112, 128, 148, 170, 194, 224, 256, 293, 334, 380, 432, 492, 556, 630, 712, 804, 908, 1026, 1152, 1296, 1454, 1632, 1828, 2048, 2292, 2560, 2858, 3190, 3554, 3959, 4404
OFFSET
1,3
FORMULA
a(n) = Sum(A117195(n,k)*(1 - k mod 2): 0<=k<n).
a(n) = A117194(n)+A010054(n) = A000009(n)-A117193(n) = A117193(n)+A003406(n).
MATHEMATICA
a[n_] := Count[IntegerPartitions[n], q_ /; EvenQ[First[q] - Length[q]] && Length[q] == Length[Union[q]]];
Array[a, 60] (* Jean-François Alcover, Oct 06 2021 *)
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 03 2006
STATUS
approved