Dirichlet convolution of triangular numbers with themselves.

Terms

a(0) =1a(1) =6a(2) =12a(3) =29a(4) =30a(5) =78a(6) =56a(7) =132a(8) =126a(9) =200a(10) =132a(11) =402a(12) =182a(13) =378a(14) =420a(15) =588a(16) =306a(17) =864a(18) =380a(19) =1050a(20) =798a(21) =902a(22) =552a(23) =1920a(24) =875a(25) =1248a(26) =1296a(27) =2002a(28) =870a(29) =2940