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Numbers n such that n +/- the product of digits of n are both palindromes.
2

%I #4 Jun 29 2014 22:09:02

%S 1,2,3,4,101,202,247,252,303,348,404,505,606,707,808,843,909,1001,

%T 2002,3003,4004,5005,6006,7007,8008,9009,10001,10101,10201,10301,

%U 10401,10501,10601,10701,10801,10901,11011,12021,13031,14041,15051,15451,16061,17071,18081,19091,20002

%N Numbers n such that n +/- the product of digits of n are both palindromes.

%e 252 + 2*5*2 = 272, a palindrome, and 252 - 2*5*2 = 232, also a palindrome. Thus 252 is a member of this sequence.

%o (PARI) rev(n)={r="";for(i=1,#digits(n),r=concat(Str(digits(n)[i]),r));return(eval(r))}

%o for(n=1,10^5,dig=digits(n);p=prod(k=1,#dig,dig[k]);mi=n-p;ma=n+p;if(rev(mi)==mi&&rev(ma)==ma,print1(n,", ")))

%Y Cf. A007954, A229546, A229547.

%K nonn,base

%O 1,2

%A _Derek Orr_, Jun 29 2014