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If n = Product (p_j^k_j) then a(n) = Product (p_j) + Product (k_j).
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%I #17 Feb 18 2022 13:05:54

%S 2,3,4,4,6,7,8,5,5,11,12,8,14,15,16,6,18,8,20,12,22,23,24,9,7,27,6,16,

%T 30,31,32,7,34,35,36,10,38,39,40,13,42,43,44,24,17,47,48,10,9,12,52,

%U 28,54,9,56,17,58,59,60,32,62,63,23,8,66,67,68,36,70,71,72,12,74,75

%N If n = Product (p_j^k_j) then a(n) = Product (p_j) + Product (k_j).

%H Seiichi Manyama, <a href="/A039696/b039696.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A007947(n) + A005361(n).

%e 14 = 2^1*7^1, a(14) = 2*7 + 1*1 = 15.

%t Array[Times @@ #1 + Times @@ #2 & @@ Transpose@ FactorInteger[#] &, 74] (* _Michael De Vlieger_, Feb 18 2022 *)

%o (PARI) a(n) = my(f=factor(n)); prod(k=1, #f~, f[k,1]) + prod(k=1, #f~, f[k,2]); \\ _Michel Marcus_, Feb 18 2022

%Y Cf. A005361, A007947.

%K nonn,easy

%O 1,1

%A _Olivier GĂ©rard_