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Search: id:A061376
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| A061376 |
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a(n) = f(n) + f(f(n)) where f(n) = 0 if n = 1 or a prime, otherwise f(n) = sum of distinct primes of n. |
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+0
1
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| 0, 0, 0, 2, 0, 5, 0, 2, 3, 7, 0, 5, 0, 12, 10, 2, 0, 5, 0, 7, 17, 13, 0, 5, 5, 23, 3, 12, 0, 17, 0, 2, 23, 19, 17, 5, 0, 31, 18, 7, 0, 17, 0, 13, 10, 30, 0, 5, 7, 7, 27, 23, 0, 5, 18, 12, 35, 31, 0, 17, 0, 47, 17, 2, 23, 18, 0, 19, 41, 23, 0, 5, 0, 55, 10, 31, 23, 23, 0, 7
(list; graph; listen)
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OFFSET
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1,4
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COMMENT
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Note that this sequence differs from A058974 at n = 26, 33, 38, 52, 62, 69, 70, 74, 76, 86, 99, etc.
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EXAMPLE
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a(14) = 12 because f(14) = 2+7 = 9 and f(9) = 3 and 9+3 = 12.
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MATHEMATICA
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f[n_Integer] := If[n == 1 || PrimeQ[n], 0, Plus@@First[ Transpose[ FactorInteger[n] ] ] ]; Table[ f[n] + f[f[n]], {n, 1, 80} ]
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CROSSREFS
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Cf. A008472, A058974.
Sequence in context: A086134 A071090 A105221 this_sequence A058974 A019962 A086131
Adjacent sequences: A061373 A061374 A061375 this_sequence A061377 A061378 A061379
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KEYWORD
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nonn
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 08 2001
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