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%I #36 Apr 01 2015 00:57:05
%S 0,2,8,101,242,404,585,909,10001,12221,14841,20402,24642,40004,44244,
%T 48884,50805,90009,96269,1000001,1030301,1080801,1210121,1244421,
%U 1298921,1440441,1478741,1690961,2004002,2234322,2468642,2484842,4000004,4050504,4410144
%N Palindromes of the form i^2 + reverse(i)^2.
%C Is 864666666468 the only term in this sequence that has an even number of digits? - _Jon E. Schoenfield_, Mar 30 2015
%H Bui Quang Tuan, <a href="/A256398/b256398.txt">Table of n, a(n) for n = 1..458</a>
%e Palindrome 585 is in the sequence because 585 = 12^2 + 21^2.
%e The smallest term that can be obtained in more than one way is 125484521 = 11020^2 + 2011^2 = 11200^2 + 211^2. Are there any terms that can be obtained in more than two ways? - _Jon E. Schoenfield_, Mar 30 2015
%t Sort@ DeleteDuplicates@ Select[Table[n^2 + FromDigits[Reverse[IntegerDigits@ n]]^2, {n, 10000}], Reverse@ IntegerDigits@ # == IntegerDigits@ # &] (* _Michael De Vlieger_, Mar 28 2015 *)
%o (PARI) rev(n)=r="";d=digits(n);for(i=1,#d,r=concat(Str(d[i]),r));eval(r)
%o v=[];for(n=0,10^4,if(rev(P=(n^2+rev(n)^2))==P,v=concat(v,P)));vecsort(v,,8) \\ _Derek Orr_, Mar 29 2015
%Y Cf. A002113 (palindromes), A056964 (n+rev(n)).
%Y Cf. A256437.
%K nonn,base
%O 1,2
%A _Bui Quang Tuan_, Mar 28 2015
%E Data corrected by _Derek Orr_, Mar 29 2015
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