a(n) = Sum_{d|n} C(n,d)*sigma(d).

Terms

a(0) =1a(1) =5a(2) =7a(3) =29a(4) =11a(5) =143a(6) =15a(7) =597a(8) =358a(9) =1675a(10) =23a(11) =15671a(12) =27a(13) =27767a(14) =19877a(15) =206197a(16) =35a(17) =858608a(18) =39a(19) =3453179a(20) =935613a(21) =8465935a(22) =47a(23) =88446975a(24) =318836a(25) =145609443a(26) =60940492a(27) =972415263a(28) =59a(29) =4271628733