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 A061376 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. 0

%I

%S 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,

%T 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,

%U 0,17,0,47,17,2,23,18,0,19,41,23,0,5,0,55,10,31,23,23,0,7

%N 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.

%C Note that this sequence differs from A058974 at n = 26, 33, 38, 52, 62, 69, 70, 74, 76, 86, 99, etc.

%e a(14) = 12 because f(14) = 2+7 = 9 and f(9) = 3 and 9+3 = 12.

%t f[n_Integer] := If[n == 1 || PrimeQ[n], 0, Plus@@First[ Transpose[ FactorInteger[n] ] ] ]; Table[ f[n] + f[f[n]], {n, 1, 80} ]

%Y Cf. A008472, A058974.

%K nonn

%O 1,4

%A _Robert G. Wilson v_, Jun 08 2001

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