Triangle of numerators of the cube of a certain lower triangular matrix.

Terms

a(0) =1a(1) =7a(2) =1a(3) =85a(4) =19a(5) =1a(6) =415a(7) =115a(8) =37a(9) =1a(10) =12019a(11) =3799a(12) =1489a(13) =61a(14) =1a(15) =13489a(16) =4669a(17) =2059a(18) =919a(19) =91a(20) =1a(21) =726301a(22) =268921a(23) =128431a(24) =64171a(25) =7669a(26) =127a(27) =1a(28) =3144919a(29) =1227199