A convolution triangle of numbers obtained from A034687.

Terms

a(0) =1a(1) =15a(2) =1a(3) =275a(4) =30a(5) =1a(6) =5500a(7) =775a(8) =45a(9) =1a(10) =115500a(11) =19250a(12) =1500a(13) =60a(14) =1a(15) =2502500a(16) =471625a(17) =44625a(18) =2450a(19) =75a(20) =1a(21) =55412500a(22) =11495000a(23) =1254000a(24) =85000a(25) =3625a(26) =90a(27) =1a(28) =1246781250a(29) =279675000