Expansion of Product_{k>=1} (1 + 7^(k-1)*x^k).

Terms

a(0) =1a(1) =1a(2) =7a(3) =56a(4) =392a(5) =3087a(6) =21952a(7) =170471a(8) =1210104a(9) =9411920a(10) =66824632a(11) =513890832a(12) =3683707839a(13) =28086110472a(14) =201122377288