A046361 Composite a(n) divided by the palindromic sum of its prime factors is a palindrome (counted with multiplicity).

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

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