A036920 Composite numbers n such that digit sum of n equals digit sum of sum of its prime factors (counted with multiplicity).
4, 22, 27, 94, 105, 114, 121, 150, 166, 202, 204, 222, 224, 265, 274, 315, 342, 346, 355, 382, 438, 445, 450, 454, 517, 526, 540, 562, 612, 634, 640, 706, 841, 852, 913, 915, 922, 1068, 1086, 1111, 1120, 1122, 1138, 1165, 1185, 1200, 1219, 1221, 1230
Offset: 1
Programs
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Mathematica
ds[n_]:=Total[IntegerDigits[n]]; t={}; Do[If[!PrimeQ[n]&&ds[n]==ds[Total[ Times@@@FactorInteger[n]]],AppendTo[t,n]],{n,4,1230}]; t (* Jayanta Basu, Jun 04 2013 *)
Extensions
Title made more precise by Sean A. Irvine, Nov 30 2020