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A046361 Composite a(n) divided by the palindromic sum of its prime factors is a palindrome (counted with multiplicity). 2

%I #14 Nov 01 2019 10:39:24

%S 4,16,27,9306,21091,26180,32648,37752,53295,158562,278784,337590,

%T 615648,667376,776556,870232,1066648,1097679,1345431,1919456,2421132,

%U 2439558,2555520,2618021,2939904,4043952,4060056,4300992,4953432,4975353,5066600,5100894,5316399

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

%H Giovanni Resta, <a href="/A046361/b046361.txt">Table of n, a(n) for n = 1..750</a>

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

%t 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 *)

%Y Cf. A046358, A046362.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998

%E Offset set to 1 and more terms added by _Giovanni Resta_, Nov 01 2019

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Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)