Triangle of coefficients in expansion of (5+7x)^n.

Terms

a(0) =1a(1) =5a(2) =7a(3) =25a(4) =70a(5) =49a(6) =125a(7) =525a(8) =735a(9) =343a(10) =625a(11) =3500a(12) =7350a(13) =6860a(14) =2401a(15) =3125a(16) =21875a(17) =61250a(18) =85750a(19) =60025a(20) =16807a(21) =15625a(22) =131250a(23) =459375a(24) =857500a(25) =900375a(26) =504210a(27) =117649a(28) =78125a(29) =765625