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a(1) = 2, and for n > 1, a(n) = n + (n/p), where p is largest prime dividing n, A006530(n).
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%I #15 Jul 08 2020 20:41:19

%S 2,3,4,6,6,8,8,12,12,12,12,16,14,16,18,24,18,24,20,24,24,24,24,32,30,

%T 28,36,32,30,36,32,48,36,36,40,48,38,40,42,48,42,48,44,48,54,48,48,64,

%U 56,60,54,56,54,72,60,64,60,60,60,72,62,64,72,96,70,72,68,72,72,80,72,96,74,76,90,80,84,84,80,96,108,84,84

%N a(1) = 2, and for n > 1, a(n) = n + (n/p), where p is largest prime dividing n, A006530(n).

%H Antti Karttunen, <a href="/A335876/b335876.txt">Table of n, a(n) for n = 1..20000</a>

%F a(n) = n + A052126(n).

%t Array[# (1 + 1/FactorInteger[#][[-1, 1]]) &, 83] (* _Michael De Vlieger_, Jul 08 2020 *)

%o (PARI) A335876(n) = if(1==n,2,n + (n/vecmax(factor(n)[, 1])));

%Y Cf. A006530, A052126, A171462, A331410, A334097, A335431 (positions of two's powers > 2).

%K nonn

%O 1,1

%A _Antti Karttunen_, Jun 28 2020