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A046352 Composite numbers whose sum of prime factors is palindromic (counted with multiplicity). 3
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 24, 27, 28, 40, 45, 48, 54, 57, 62, 85, 102, 106, 116, 121, 123, 182, 194, 218, 259, 260, 278, 292, 298, 305, 308, 312, 351, 358, 366, 370, 388, 403, 413, 415, 428, 440, 444, 483, 495, 498, 508, 528, 548, 568, 575, 590 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..2014

EXAMPLE

116 = 2 * 2 * 29 -> 2 + 2 + 29 = 33 and 33 is a palindrome.

MAPLE

n := 1 ;

for i from 2 to 30000 do

    if not isprime(i) then

        sof := A001414(i) ;

        if isA002113(sof) then

            printf("%d %d\n", n, i) ;

            n := n+1 ;

        end if;

    end if;

end do: # R. J. Mathar, Sep 09 2015

MATHEMATICA

palQ[n_]:=Reverse[x=IntegerDigits[n]]==x; Select[Range[4, 590], !PrimeQ[#]&&palQ[Total[Times@@@FactorInteger[#]]]&] (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A046353, A046354.

Sequence in context: A199009 A070807 A246282 * A046355 A163122 A202259

Adjacent sequences:  A046349 A046350 A046351 * A046353 A046354 A046355

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998.

STATUS

approved

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Last modified May 23 19:46 EDT 2017. Contains 286926 sequences.