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PROJECT EULER · #0545

Faulhaber's Formulas

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The sum of the kth powers of the first n positive integers can be expressed as a polynomial of degree k+1 with rational coefficients, the Faulhaber's Formulas:
1k+2k+...+nk=i=1nik=i=1k+1aini=a1n+a2n2+...+aknk+ak+1nk+1,
where ai's are rational coefficients that can be written as reduced fractions pi/qi (if ai=0, we shall consider qi=1).

For example, 14+24+...+n4=130n+13n3+12n4+15n5.

Define D(k) as the value of q1 for the sum of kth powers (i.e. the denominator of the reduced fraction a1).
Define F(m) as the mth value of k1 for which D(k)=20010.
You are given D(4)=30 (since a1=1/30), D(308)=20010, F(1)=308, F(10)=96404.

Find F(105).

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