A036350 - OEIS

%I #20 Jul 15 2020 06:19:07

%S 6,10,12,14,20,22,24,26,27,28,34,38,40,44,45,46,48,52,54,56,58,62,63,

%T 68,74,75,76,80,82,86,88,90,92,94,96,99,104,105,106,108,112,116,117,

%U 118,122,124,125,126,134,136,142,146,147,148,150,152,153,158,160,164

%N Composite numbers such that the sum of the prime factors is odd (counted with multiplicity).

%e 44 = 2 * 2 * 11 -> sum = 15 -> 15 is odd.

%t okQ[n_]:=!PrimeQ[n]&&OddQ[Total[Flatten[Table[First[#],{Last[#]}]&/@ FactorInteger[n]]]]; Select[Range[2,200],okQ] (* _Harvey P. Dale_, Dec 18 2011 *)

%Y Cf. A001414, A046363, A036349.

%Y Subsequence of A335657.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Dec 15 1998