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

4, 5, 6, 6, 13, 14, 15, 16, 16, 18, 17, 17, 40, 22, 50, 30, 25, 103, 57, 42, 35, 24, 17, 133, 25, 52, 77, 104, 36, 43, 21, 25, 134, 105, 31, 59, 40, 44, 229, 37, 84, 26, 34, 106, 108, 20, 112, 114, 45, 118, 33, 24, 29, 106, 24, 315, 60, 38, 49, 45, 30, 23, 38, 108, 242, 78

Offset

1,1

Links

Table of n, a(n) for n=1..66.

Formula

a(n) = A001414(A032350(1+n)). - R. J. Mathar, Sep 09 2015

Example

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

Mathematica

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 *)

Crossrefs

Cf. A046343, A046344.

Sequence in context: A273777 A023846 A338625 * A325103 A004445 A174630

Adjacent sequences: A046342 A046343 A046344 * A046346 A046347 A046348

Keyword

nonn,base

Author

Patrick De Geest, Jun 15 1998

Extensions

Offset set to 1. - R. J. Mathar, Sep 09 2015

Status

approved