Triangle of coefficients of a polynomial sequence related to the coloring of labeled graphs.

Terms

a(0) =1a(1) =0a(2) =1a(3) =0a(4) =-1a(5) =2a(6) =0a(7) =5a(8) =-12a(9) =8a(10) =0a(11) =-79a(12) =208a(13) =-192a(14) =64a(15) =0a(16) =3377a(17) =-9520a(18) =10240a(19) =-5120a(20) =1024a(21) =0a(22) =-362431a(23) =1079744a(24) =-1282560a(25) =778240a(26) =-245760a(27) =32768a(28) =0a(29) =93473345