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A046361 Composite a(n) divided by the palindromic sum of its prime factors is a palindrome (counted with multiplicity). 2
4, 16, 27, 9306, 21091, 26180, 32648, 37752, 53295, 158562, 278784, 337590, 615648, 667376, 776556, 870232, 1066648, 1097679, 1345431, 1919456, 2421132, 2439558, 2555520, 2618021, 2939904, 4043952, 4060056, 4300992, 4953432, 4975353, 5066600, 5100894, 5316399 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..750

EXAMPLE

9306 = 2 * 3 * 3 * 11 * 47 -> Sum of factors is palindrome 66 -> 9306 / 66 = 141 and quotient 141 is also palindromic.

MATHEMATICA

palQ[n_]:=Reverse[x=IntegerDigits[n]]==x; t={}; Do[If[!PrimeQ[n]&&IntegerQ[z=n/(y=Total[Times@@@FactorInteger[n]])]&&And@@palQ/@{y, z}, AppendTo[t, n]], {n, 4, 3*10^6}]; t (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A046358, A046362.

Sequence in context: A227609 A219338 A275211 * A228167 A017569 A161335

Adjacent sequences:  A046358 A046359 A046360 * A046362 A046363 A046364

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998

EXTENSIONS

Offset set to 1 and more terms added by Giovanni Resta, Nov 01 2019

STATUS

approved

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Last modified May 24 18:00 EDT 2020. Contains 334574 sequences. (Running on oeis4.)