Numerator of sum of -2nd powers of divisors of n.

Terms

a(0) =1a(1) =5a(2) =10a(3) =21a(4) =26a(5) =25a(6) =50a(7) =85a(8) =91a(9) =13a(10) =122a(11) =35a(12) =170a(13) =125a(14) =52a(15) =341a(16) =290a(17) =455a(18) =362a(19) =273a(20) =500a(21) =305a(22) =530a(23) =425a(24) =651a(25) =425a(26) =820a(27) =75a(28) =842a(29) =13