Expansion of Product_{i>=1, j>=0} (1 + x^(i * 7^j)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =3a(6) =4a(7) =6a(8) =7a(9) =9a(10) =12a(11) =14a(12) =18a(13) =22a(14) =28a(15) =34a(16) =41a(17) =50a(18) =60a(19) =72a(20) =86a(21) =105a(22) =124a(23) =146a(24) =174a(25) =204a(26) =240a(27) =282a(28) =332a(29) =386