Denominator of sum of -7th powers of divisors of n.

Terms

a(0) =1a(1) =128a(2) =2187a(3) =16384a(4) =78125a(5) =23328a(6) =823543a(7) =2097152a(8) =4782969a(9) =5000000a(10) =19487171a(11) =8957952a(12) =62748517a(13) =13176688a(14) =56953125a(15) =268435456a(16) =410338673a(17) =204073344a(18) =893871739a(19) =640000000a(20) =1801088541a(21) =623589472