Dirichlet convolution of 3^(n-1) with sigma(n).

Terms

a(0) =1a(1) =6a(2) =13a(3) =43a(4) =87a(5) =294a(6) =737a(7) =2304a(8) =6610a(9) =19962a(10) =59061a(11) =178111a(12) =531455a(13) =1596558a(14) =4783371a(15) =14355733a(16) =43046739a(17) =129161004a(18) =387420509a(19) =1162321341a(20) =3486787421a(21) =10460530422a(22) =31381059633a(23) =94143721320a(24) =282429536998a(25) =847290203850