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A036346 Composites n such that A001414(n) is odd and divides n.

%I A036346 #15 Jul 16 2020 02:38:31
%S A036346 27,105,150,180,231,588,627,650,805,840,897,945,1008,1100,1122,1134,
%T A036346 1581,1755,2079,2106,2625,2660,2800,2958,2964,2967,2970,3055,3125,
%U A036346 3150,3432,3564,3750,3861,4000,4070,4185,4500,4543,4760,4800,5292,5304,5355
%N A036346 Composites n such that A001414(n) is odd and divides n.
%H A036346 Robert Israel, <a href="/A036346/b036346.txt">Table of n, a(n) for n = 1..10000</a>
%e A036346 5445 = 3*3*5*11*11 -> sum = 3+3+5+11+11 = 33 (=odd) so 33 divides 5445 exactly.
%p A036346 filter:= proc(n) local F,s;
%p A036346   if isprime(n) then return false fi;
%p A036346   F:=  ifactors(n)[2];
%p A036346   s:= add(t[1]*t[2],t=F);
%p A036346   s::odd and ( n mod s = 0)
%p A036346 end proc:
%p A036346 select(filter, [$1..10000]); # _Robert Israel_, Jul 15 2020
%t A036346 With[{s = Map[{#, Total[Times @@@ FactorInteger[#]]} &, Select[Range[4, 6000], CompositeQ]]}, Select[s, Mod[#1, #2] == 0 && OddQ[#2] & @@ # &][[All, 1]] ] (* _Michael De Vlieger_, Jul 15 2020 *)
%Y A036346 Cf. A001414, A046346, A036345.
%K A036346 nonn
%O A036346 1,1
%A A036346 _Patrick De Geest_, Dec 15 1998
%E A036346 Name and offset corrected by _Robert Israel_, Jul 15 2020