A083718 - OEIS

%I #5 Aug 11 2016 19:06:05

%S 2,4,6,5,10,8,14,9,10,12,22,14,26,20,18,15,34,20,38,24,26,30,46,26,28,

%T 36,26,30,58,34,62,33,42,48,38,34,74,56,50,42,82,48,86,54,48,66,94,50,

%U 54,52,64,60,106,56,64,60,72,82,118,64,122,92,68,63,74,72,134,84,90,74

%N (greatest prime <= n) + (greatest prime factor of n).

%C a(n) = A007917(n) + A006530(n).

%t Join[{2},Table[If[PrimeQ[n],n,NextPrime[n,-1]]+FactorInteger[n][[-1,1]],{n,2,70}]] (* _Harvey P. Dale_, Aug 11 2016 *)

%Y Cf. A083714, A083715, A083716, A083717.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, May 04 2003