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A351366
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a(n) = Sum_{p|n, p prime} p^p.
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2
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0, 4, 27, 4, 3125, 31, 823543, 4, 27, 3129, 285311670611, 31, 302875106592253, 823547, 3152, 4, 827240261886336764177, 31, 1978419655660313589123979, 3129, 823570, 285311670615, 20880467999847912034355032910567, 31, 3125, 302875106592257
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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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G.f.: Sum_{k>=1} (prime(k) * x)^prime(k)/(1 - x^prime(k)). - Seiichi Manyama, Mar 02 2022
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EXAMPLE
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a(6) = 31; a(6) = Sum_{p|6, p prime} p^p = 2^2 + 3^3 = 31.
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PROG
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(PARI) my(N=40, x='x+O('x^N)); concat(0, Vec(sum(k=1, N, isprime(k)*(k*x)^k/(1-x^k)))) \\ Seiichi Manyama, Mar 02 2022
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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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