A161656 - OEIS

%I #19 May 26 2016 02:20:14

%S 0,2,3,4,5,5,7,8,9,7,11,10,13,9,8,16,17,15,19,14,20,13,23,20,25,15,27,

%T 27,29,30,31,32,28,19,24,35,37,21,32,35,41,36,43,39,40,25,47,45,49,49,

%U 40,45,53,50,48,54,44,31,59,60,61,33,60,64,54,64,67,57,52,70,71,70,73

%N The largest multiple of {the sum of the distinct prime divisors of n} that is <=n.

%C a(n)=n iff n belongs to A089352. - _Ivan Neretin_, May 25 2016

%H Ivan Neretin, <a href="/A161656/b161656.txt">Table of n, a(n) for n = 1..10000</a>

%p A161656 := proc(n)

%p     local sd;

%p     if n <= 1 then

%p         0;

%p     else

%p         sd := A008472(n) ;

%p         sd*floor(n/sd) ;

%p     end if;

%p end proc: # _R. J. Mathar_, Mar 14 2014

%t Join[{0}, Table[Floor[#1/#2]*#2 &[n, Plus @@ FactorInteger[n][[All, 1]]], {n, 2, 73}] ](* _Ivan Neretin_, May 25 2016 *)

%Y Cf. A008472, A161657.

%K nonn

%O 1,2

%A _Leroy Quet_, Jun 15 2009

%E More terms from _Sean A. Irvine_, Sep 29 2009