a(n) = sigma_8(n^2)/sigma_4(n^2).

Terms

a(0) =1a(1) =241a(2) =6481a(3) =61681a(4) =390001a(5) =1561921a(6) =5762401a(7) =15790321a(8) =42521761a(9) =93990241a(10) =214344241a(11) =399754561a(12) =815702161a(13) =1388738641a(14) =2527596481a(15) =4042322161a(16) =6975673921a(17) =10247744401a(18) =16983432721a(19) =24055651681a(20) =37346120881a(21) =51656962081a(22) =78310705441a(23) =102337070401