cp's OEIS Frontend

A366080 Numbers that give a perfect power when added to their reverse.

%I A366080 #80 Oct 26 2023 08:32:19
%S A366080 2,4,8,29,38,47,56,65,74,83,92,110,122,143,164,198,221,242,263,297,
%T A366080 320,341,362,396,440,461,495,560,594,693,792,891,990,1030,1120,1210,
%U A366080 1300,10100,10148,10340,10395,10403,10683,10908,10980,11138,11330,11385,11673
%N A366080 Numbers that give a perfect power when added to their reverse.
%H A366080 Robert Israel, <a href="/A366080/b366080.txt">Table of n, a(n) for n = 1..2000</a>
%e A366080 8 is a term because 8 + 8 = 16 = 2^4 or 4^2.
%e A366080 10340 is a term because 10340 + 04301 = 14641 is a perfect power 11^4.
%p A366080 filter:= proc(n) local L,i,x;
%p A366080   L:= convert(n,base,10);
%p A366080   x:= add(10^(i-1)*L[-i],i=1..nops(L));
%p A366080   igcd(ifactors(n+x)[2][..,2])>1;
%p A366080 end proc:
%p A366080 select(filter, [$1..20000]); # _Robert Israel_, Oct 24 2023
%o A366080 (PARI) isok(k) = ispower(k + fromdigits(Vecrev(digits(k)))); \\ _Michel Marcus_, Oct 24 2023
%Y A366080 Cf. A001597, A056964.
%K A366080 nonn,base
%O A366080 1,1
%A A366080 _Tanmaya Mohanty_, Oct 24 2023
%E A366080 More terms from _Robert Israel_, Oct 24 2023