view my set
we remember that
n=1∑∞nsCh(n)=−2ζ(2s)+ζ(s)
consider Cs(n)=(Ch∗1)(n)=d∣n∑Ch(d)
so, if d is a perfect square it is -1, 1 otherwise. if there are k perfect square divisors, there are τ(n)−k non-square divisor. add them and it is τ(n)−2k.
let k be a function of n. It is multiplicative. So we can compute for prime powers
k(pa)=d2∣pa∑d0=10+(p2)0+(p4)0+....⎝⎛p2⌊2a⌋⎠⎞0=⌊2a⌋+1
we have
n=1∑∞nsCh(n)n=1∑∞ns1=n=1∑∞nsτ(n)−2n=1∑∞nsk(n)
−2ζ(s)ζ(2s)+ζ2(s)=ζ2(s)−2n=1∑∞nsk(n)
n=1∑∞nsk(n)=ζ(s)ζ(2s)
Lets try to compute the summation using the fact it is multpicative
p=prime∏a≥0∑pask(pa)=p=prime∏a≥0∑pas⌊2a⌋+1=p=prime∏(ps−1)2(ps+1)p3s=p∏(1−p−s)211−p−2s1−p−s=ζ2(s)ζ(s)ζ(2s)=ζ(s)ζ(2s)
so we get
s=s
again!!!
#Calculus
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The combo part was not found by me but @Andrew Ellinor so he gets the credit for that.
He was not sure wether or not he was correct but this proves that k(n)=i=1∏ω(n)(⌊2ki⌋+1) if n=p1k1p2k2.....pω(n)kω(n)
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Well he is correct.