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A046348
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Composite palindromes divisible by the sum of their prime factors (counted with multiplicity).
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3
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4, 646, 2772, 5445, 8778, 30303, 48384, 50505, 54145, 63336, 77077, 117711, 219912, 234432, 239932, 255552, 272272, 294492, 535535, 585585, 636636, 717717, 825528, 888888, 951159, 999999, 1103011, 1112111, 1345431, 2248422, 2267622
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2)=646 : 2*17*19 -> 2 + 17 + 19 = 38 and 646 / 38 = 17.
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MATHEMATICA
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t={}; Do[If[!PrimeQ[n]&&Reverse[x=IntegerDigits[n]]==x&&IntegerQ[n/Total[Times@@@FactorInteger[n]]], AppendTo[t, n]], {n, 4, 2.5*10^6}]; t (* Jayanta Basu, Jun 04 2013 *)
cpdQ[n_]:=CompositeQ[n]&&PalindromeQ[n]&&Divisible[n, Total[ Flatten[ Table[ #[[1]], #[[2]]]&/@FactorInteger[n]]]]; Select[Range[23*10^5], cpdQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 01 2018 *)
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PROG
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(PARI) See PARI link.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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