A convolution triangle of numbers obtained from A034789.

Terms

a(0) =1a(1) =21a(2) =1a(3) =546a(4) =42a(5) =1a(6) =15561a(7) =1533a(8) =63a(9) =1a(10) =466830a(11) =54054a(12) =2961a(13) =84a(14) =1a(15) =14471730a(16) =1885338a(17) =124740a(18) =4830a(19) =105a(20) =1a(21) =458960580a(22) =65542932a(23) =4977882a(24) =236880a(25) =7140a(26) =126a(27) =1a(28) =14801478705a(29) =2277656901