OFFSET
0,6
REFERENCES
George E. Andrews, The Theory of Partitions, Addison-Wesley, Reading, Mass., 1976.
FORMULA
G.f.: Sum((-1)^(k+1)*x^((3*k^2+3*k)/2)/(1+x^k), k>=1)/Product(1-x^k, k>=1). - Vladeta Jovovic, Dec 20 2004
EXAMPLE
a(7)=4 because the only partitions of 7 with positive even rank are 7 (rank=6), 61 (rank=4), 511 (rank=2) and 43 (rank=2).
MATHEMATICA
Table[Count[Max[#]-Length[#]&/@IntegerPartitions[n], _?(EvenQ[#] && Positive[#]&)], {n, 50}] (* Harvey P. Dale, Feb 26 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Dec 12 2004
EXTENSIONS
More terms from Joerg Arndt, Oct 07 2012
Offset changed to 0 by Georg Fischer, Dec 23 2023
STATUS
approved