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A046357 Composite palindromes with only palindromic prime factors whose sum is palindromic (counted with multiplicity). 2

%I

%S 4,6,8,9,121,1331,5445,10201,13231,14641,15251,18281,19291,31613,

%T 35653,37673,38683,52525,59895,1030301,1336331,3192913,8117118,

%U 104060401,134969431,286121682,319464913,677707776

%N Composite palindromes with only palindromic prime factors whose sum is palindromic (counted with multiplicity).

%F A046355 INTERSECT A002113. - _R. J. Mathar_, Sep 09 2015

%e 319464913 = 10301 * 31013 and 10301 + 31013 = 41314 and all are palindromic.

%t palQ[n_]:= Reverse[x=IntegerDigits[n]] == x; t={}; Do[If[!PrimeQ[n] && And@@palQ/@Join[{n, Total[Times@@@(x=FactorInteger[n])]}, First/@x], AppendTo[t,n]],{n, 2, 3.2*10^6}]; t (* _Jayanta Basu_, Jun 05 2013 *)

%Y Cf. A046355, A046356.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998.

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Last modified December 13 12:49 EST 2018. Contains 318086 sequences. (Running on oeis4.)