a(n) = sigma_8(n), the sum of the 8th powers of the divisors of n.

Terms

a(0) =1a(1) =257a(2) =6562a(3) =65793a(4) =390626a(5) =1686434a(6) =5764802a(7) =16843009a(8) =43053283a(9) =100390882a(10) =214358882a(11) =431733666a(12) =815730722a(13) =1481554114a(14) =2563287812a(15) =4311810305a(16) =6975757442a(17) =11064693731a(18) =16983563042a(19) =25700456418a(20) =37828630724a(21) =55090232674a(22) =78310985282a(23) =110523825058a(24) =152588281251