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A046345 Sum of the prime factors of the palindromic composite numbers (counted with multiplicity). 2

%I

%S 4,5,6,6,13,14,15,16,16,18,17,17,40,22,50,30,25,103,57,42,35,24,17,

%T 133,25,52,77,104,36,43,21,25,134,105,31,59,40,44,229,37,84,26,34,106,

%U 108,20,112,114,45,118,33,24,29,106,24,315,60,38,49,45,30,23,38,108,242,78

%N Sum of the prime factors of the palindromic composite numbers (counted with multiplicity).

%F a(n) = A001414(A032350(1+n)). - _R. J. Mathar_, Sep 09 2015

%e a(60)=45 because 666 = 2 * 3 * 3 * 37 and 45 = 2 + 3 + 3 + 37.

%t t={}; Do[If[!PrimeQ[n]&&Reverse[x=IntegerDigits[n]]==x,AppendTo[t,Total[Times@@@FactorInteger[n]]]],{n,4,740}]; t (* _Jayanta Basu_, Jun 04 2013 *)

%Y Cf. A046343, A046344.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998

%E Offset set to 1. - _R. J. Mathar_, Sep 09 2015

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Last modified February 20 06:26 EST 2019. Contains 320332 sequences. (Running on oeis4.)