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A256437 Nonnegative integers i such that i^2 + reverse(i)^2 is a palindrome.

%I A256437 #28 Apr 10 2015 09:46:39
%S A256437 0,1,2,10,11,12,20,21,30,100,101,102,110,111,120,200,201,210,220,300,
%T A256437 310,1000,1001,1002,1010,1011,1012,1020,1021,1022,1100,1101,1102,1110,
%U A256437 1111,1120,1200,1201,1210,1300,2000,2001,2010,2011,2100,2101,2110,2200,2201
%N A256437 Nonnegative integers i such that i^2 + reverse(i)^2 is a palindrome.
%C A256437 This sequence generates A256398.
%H A256437 Bui Quang Tuan, <a href="/A256437/b256437.txt">Table of n, a(n) for n = 1..554</a>
%e A256437 12 is in the sequence because 12^2 + 21^2 = 585, a palindrome.
%t A256437 palQ[n_] := Reverse@ IntegerDigits@ n == IntegerDigits@ n; Select[
%t A256437 Range@2210, palQ[#^2 + FromDigits[Reverse[IntegerDigits@ #]]^2] &] (* _Michael De Vlieger_, Mar 29 2015 *)
%o A256437 (PARI) rev(n)=r=""; d=digits(n); for(i=1, #d, r=concat(Str(d[i]), r)); eval(r);
%o A256437 ispal(n) = d = digits(n); Vecrev(d) == d;
%o A256437 isok(n) = ispal(n^2+rev(n)^2) \\ _Michel Marcus_, Apr 01 2015
%o A256437 (Python)
%o A256437 A256437_list = [i for i in range(10**6) if str(i**2 + int(str(i)[::-1])**2) == str(i**2 + int(str(i)[::-1])**2)[::-1]] # _Chai Wah Wu_, Apr 09 2015
%Y A256437 Cf. A002113, A004086, A256398.
%K A256437 nonn,base
%O A256437 1,3
%A A256437 _Bui Quang Tuan_, Mar 29 2015