A convolution triangle of numbers obtained from A034904.

Terms

a(0) =1a(1) =28a(2) =1a(3) =980a(4) =56a(5) =1a(6) =37730a(7) =2744a(8) =84a(9) =1a(10) =1531838a(11) =130340a(12) =5292a(13) =112a(14) =1a(15) =64337196a(16) =6136956a(17) =299782a(18) =8624a(19) =140a(20) =1a(21) =2766499428a(22) =288408120a(23) =16120314a(24) =568008a(25) =12740a(26) =168a(27) =1a(28) =121034349975a(29) =13561837212