OFFSET
1,6
LINKS
Noureddine Chair, Partition Identities From Partial Supersymmetry, arXiv:hep-th/0409011v1, 2004.
FORMULA
G.f.: product_{k>0}(1+x^k)/(1-(-1)^k*x^(2*k^2-k)).
EXAMPLE
a(15)=20 because 15 =13+2 =12+3 =11+4 =10+5 =10+3+2 =9+6=9+4+2 =8+7 =8+5+2 =8+4+3 =7+6+2 =7+5+3 =6+5+4 =6+4+3+2 =9+2+2+2 =7+2+2+2+2 =6+3+2+2+2 =5+4+2+2+2 =4+3+2+2+2+2 =3+2+2+2+2+2+2"
MAPLE
series(product((1+x^k)/(1-(-1)^k*x^(2*k^2-k)), k=1..100), x=0, 100);
CROSSREFS
KEYWORD
nonn
AUTHOR
Noureddine Chair, Nov 29 2004
STATUS
approved