Inverse of a Delannoy related triangle.

Terms

a(0) =1a(1) =-3a(2) =1a(3) =2a(4) =-5a(5) =1a(6) =-2a(7) =10a(8) =-7a(9) =1a(10) =2a(11) =-14a(12) =22a(13) =-9a(14) =1a(15) =-2a(16) =18a(17) =-46a(18) =38a(19) =-11a(20) =1a(21) =2a(22) =-22a(23) =78a(24) =-106a(25) =58a(26) =-13a(27) =1a(28) =-2a(29) =26