Column 1 of triangle A055288.

Terms

a(0) =1a(1) =-1a(2) =1a(3) =0a(4) =-3a(5) =5a(6) =9a(7) =-44a(8) =-50a(9) =545a(10) =572a(11) =-9890a(12) =-13263a(13) =251236a(14) =490208a(15) =-8309897a(16) =-25084529a(17) =340735734a(18) =1618199204a(19) =-16683530000a(20) =-123071639020a(21) =922641297931