a(n) = coefficient of x^n*y^n in Product_{n>=1} (1 - (x^n + y^n))^3.

Terms

a(0) =1a(1) =6a(2) =-12a(3) =-6a(4) =6a(5) =-12a(6) =-12a(7) =96a(8) =24a(9) =-134a(10) =-192a(11) =114a(12) =736a(13) =282a(14) =-792a(15) =-1532a(16) =-270a(17) =1932a(18) =2004a(19) =-96a(20) =-3654a(21) =-6910a(22) =-5532a(23) =4836a(24) =21500a(25) =23454a(26) =11850a(27) =-8216a(28) =-43998a(29) =-57744