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%I #13 Nov 30 2020 22:41:02
%S 27,105,121,265,315,355,445,517,841,913,915,1111,1165,1185,1219,1221,
%T 1239,1255,1345,1363,1507,1633,1903,2067,2101,2155,2173,2209,2227,
%U 2245,2265,2335,2409,2515,2533,2605,2965,3091,3129,3219,3235,3417,3505,3507
%N Odd composite numbers n such that the digit sum of n equals digit sum of sum of its prime factors (counted with multiplicity).
%t ds[n_]:=Total[IntegerDigits[n]]; t={}; Do[If[!PrimeQ[n]&&ds[n]==ds[Total[ Times@@@FactorInteger[n]]],AppendTo[t,n]],{n,9,3508,2}]; t (* _Jayanta Basu_, Jun 04 2013 *)
%Y Cf. A006753, A036920, A019506.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Jan 04 1999
%E Title reworded by _Sean A. Irvine_, Nov 30 2020
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