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 A174147 a(n) = n-th sum{p-1|p is prime and divisor of n} plus n-th product{p-1|p is prime and divisor of n} 0

%I

%S 0,2,4,2,8,5,12,2,4,9,20,5,24,13,14,2,32,5,36,9,20,21,44,5,8,25,4,13,

%T 56,15,60,2,32,33,34,5,72,37,38,9,80,21,84,21,14,45,92,5,12,9,50,25,

%U 104,5,54,13,56,57,116,15,120,61,20,2,64,33,132,33,68,35,140,5,144,73,14

%N a(n) = n-th sum{p-1|p is prime and divisor of n} plus n-th product{p-1|p is prime and divisor of n}

%C for n=1 sum{p-1|p is prime and divisor of 1} is zero.

%F a(n)=A055631(n)+A173557(n).

%Y Cf. A055631, A173557.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 09 2010

%E Formula index corrected, a 62 replaced by 64 - _R. J. Mathar_, Apr 25 2010.

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Last modified September 16 21:28 EDT 2021. Contains 347473 sequences. (Running on oeis4.)