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%I #25 Dec 15 2017 17:36:02
%S 2,4,6,4,10,5,14,4,6,7,22,5,26,9,8,4,34,5,38,7,10,13,46,5,10,15,6,9,
%T 58,7,62,4,14,19,12,5,74,21,16,7,82,9,86,13,8,25,94,5,14,7,20,15,106,
%U 5,16,9,22,31,118,7,122,33,10,4,18,13,134,19,26,9,142,5,146,39,8,21,18,15
%N a(n) = sum of smallest and largest prime factors of n, for n>1; a(1)=2.
%C If n is prime, a(n) = 2n; the only prime factor, n itself, is taken as both the "smallest" and "largest" prime factor of n. - _Jon E. Schoenfield_, Jan 14 2015
%H R. Zumkeller, <a href="/A074320/b074320.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A020639(n) + A006530(n).
%t f[n_]:=Transpose[FactorInteger[n]][[1]];Table[First[f[n]]+Last[f[n]],{n,200}] (* _Vladimir Joseph Stephan Orlovsky_, Apr 08 2011 *)
%o (PARI) a(n) = if (n==1, 2, my(f=factor(n)); f[1,1] + f[#f~,1]); \\ _Michel Marcus_, Jan 14 2015
%Y Cf. A046665, A066048, A130064, A130065.
%K easy,nonn
%O 1,1
%A _Jason Earls_, Sep 26 2002
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