Triangle T(n,0)=0 and T(n,k) = -A028421(n-1,k-1), 0<k<=n.

Terms

a(0) =0a(1) =0a(2) =-1a(3) =0a(4) =-1a(5) =-2a(6) =0a(7) =-2a(8) =-6a(9) =-3a(10) =0a(11) =-6a(12) =-22a(13) =-18a(14) =-4a(15) =0a(16) =-24a(17) =-100a(18) =-105a(19) =-40a(20) =-5a(21) =0a(22) =-120a(23) =-548a(24) =-675a(25) =-340a(26) =-75a(27) =-6a(28) =0a(29) =-720