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A342449
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a(n) = Sum_{k=1..n} gcd(k,n)^k.
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4
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1, 5, 29, 262, 3129, 46705, 823549, 16777544, 387421251, 10000003469, 285311670621, 8916100581446, 302875106592265, 11112006826387025, 437893890391180013, 18446744073743123788, 827240261886336764193, 39346408075299116257065
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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) = p-1 + p^p = A231712(p).
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MATHEMATICA
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a[n_] := Sum[GCD[k, n]^k, {k, 1, n}]; Array[a, 20] (* Amiram Eldar, Mar 13 2021 *)
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PROG
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(PARI) a(n) = sum(k=1, n, gcd(k, n)^k);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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