Expansion of Sum_{1<=i<=j<=k} q^(i+j+k)/( (1-q^i)*(1-q^j)*(1-q^k) )^2.

Terms

a(0) =1a(1) =7a(2) =27a(3) =77a(4) =181a(5) =378a(6) =707a(7) =1254a(8) =2052a(9) =3290a(10) =4928a(11) =7371a(12) =10381a(13) =14756a(14) =19818a(15) =27158a(16) =35139a(17) =46683a(18) =58806a(19) =76146a(20) =93555a(21) =119092a(22) =143222a(23) =178983a(24) =212408a(25) =261261a(26) =305046a(27) =371931a(28) =428156a(29) =515592