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A342395
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a(n) = Sum_{k=1..n} k^(n/gcd(k,n)).
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2
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1, 3, 12, 90, 1305, 15713, 376768, 6163324, 176787369, 3769360335, 142364319636, 3152514811878, 154718778284161, 4340009168261557, 210971169749009040, 7281661102087491416, 435659030617933827153, 14181101408651996188995
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OFFSET
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1,2
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LINKS
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FORMULA
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If p is prime, a(p) = A121706(p) + p.
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MATHEMATICA
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a[n_] := Sum[k^(n/GCD[k, n]), {k, 1, n}]; Array[a, 18] (* Amiram Eldar, Mar 10 2021 *)
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PROG
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(PARI) a(n) = sum(k=1, n, k^(n/gcd(k, n)));
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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