Triangle, read by rows, where T(0,0) = 1, T(n,k) = (-1)^n*(2n+1)*T(n-1,k) - T(n-1,k-1).

Terms

a(0) =1a(1) =-3a(2) =-1a(3) =-15a(4) =-2a(5) =1a(6) =105a(7) =29a(8) =-5a(9) =-1a(10) =945a(11) =156a(12) =-74a(13) =-4a(14) =1a(15) =-10395a(16) =-2661a(17) =658a(18) =118a(19) =-7a(20) =-1a(21) =-135135a(22) =-24198a(23) =11215a(24) =876a(25) =-209a(26) =-6a(27) =1a(28) =2027025a(29) =498105