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PROJECT EULER · #0722

Slowly Converging Series

Statement only · UnsolvedOriginal problem ↗

For a non-negative integer k, define Ek(q)=n=1σk(n)qn where σk(n)=dndk is the sum of the k-th powers of the positive divisors of n.

It can be shown that, for every k, the series Ek(q) converges for any 0<q<1.

For example,
E1(1124)=3.872155809243e2
E3(1128)=2.767385314772e10
E7(11215)=6.725803486744e39
All the above values are given in scientific notation rounded to twelve digits after the decimal point.

Find the value of E15(11225).
Give the answer in scientific notation rounded to twelve digits after the decimal point.

Write-up coming later

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