G.f. A(x) satisfies: [x^k] A(x) / (1-x)^n = 0 for k = n*(n+1)/2 + 1 through k = (n+1)*(n+2)/2 for n >= 0.

A305605

G.f. A(x) satisfies: [x^k] A(x) / (1-x)^n = 0 for k = n*(n+1)/2 + 1 through k = (n+1)*(n+2)/2 for n >= 0.

Terms

    a(0) =1a(1) =0a(2) =-1a(3) =0a(4) =-2a(5) =2a(6) =0a(7) =-7a(8) =14a(9) =-7a(10) =0a(11) =-37a(12) =111a(13) =-111a(14) =37a(15) =0a(16) =-268a(17) =1072a(18) =-1608a(19) =1072a(20) =-268a(21) =0a(22) =-2496a(23) =12480a(24) =-24960a(25) =24960a(26) =-12480a(27) =2496a(28) =0a(29) =-28612

External references