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A345299
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a(n) = Sum_{p|n} p^pi(p).
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1
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0, 2, 9, 2, 125, 11, 2401, 2, 9, 127, 161051, 11, 4826809, 2403, 134, 2, 410338673, 11, 16983563041, 127, 2410, 161053, 1801152661463, 11, 125, 4826811, 9, 2403, 420707233300201, 136, 25408476896404831, 2, 161060, 410338675, 2526, 11, 6582952005840035281, 16983563043
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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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a(p) = p^pi(p) for p prime.
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EXAMPLE
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a(10) = Sum_{p|10} p^pi(p) = 2^1 + 5^3 = 127.
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MATHEMATICA
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Table[Sum[k^PrimePi[k] (PrimePi[k] - PrimePi[k - 1]) (1 - Ceiling[n/k] + Floor[n/k]), {k, n}], {n, 50}]
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PROG
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(Python)
from sympy import primefactors, primepi
def A345299(n): return sum(p**primepi(p) for p in primefactors(n)) # Chai Wah Wu, Jun 13 2021
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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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