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%I #14 Mar 05 2024 14:42:28
%S 0,211,220,235,20403,111416,1011231,3444142,10003400,22303600,
%T 31151021,53231032,121542025,126423126,202032110,243425212,302434003,
%U 311544033,324231521,334130241,375607602,406221650,561620561,662033363,1053045074
%N Numbers k such that concatenating k and the sum of the digits of k raised to their own power (A045503) produces a square.
%e 235 is a term because 2^2 + 3^3 + 5^5 = 3156 and 2353156 = 1534^2.
%o (PARI) f(n)=if(n, n=digits(n); sum(i=1, #n, n[i]^n[i]), 1); \\ A045503
%o isok(k) = issquare(fromdigits(concat(digits(k), digits(f(k))))); \\ _Michel Marcus_, Mar 05 2024
%Y Cf. A045503, A108302.
%K base,nonn
%O 1,2
%A _Jason Earls_, Jul 04 2005
%E More terms from _Ryan Propper_, Jul 07 2005