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

Terms

a(0) =1a(1) =0a(2) =0a(3) =-2a(4) =-2a(5) =-2a(6) =0a(7) =2a(8) =2a(9) =4a(10) =-2a(11) =2a(12) =0a(13) =4a(14) =-2a(15) =4a(16) =6a(17) =4a(18) =4a(19) =-2a(20) =-10a(21) =-12a(22) =-12a(23) =-16a(24) =-14a(25) =6a(26) =6a(27) =-4a(28) =16a(29) =22