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%I #10 Dec 20 2023 20:15:35
%S 1,2,3,11,12,14,16,32,33,37,47,76,101,108,126,131,134,144,168,188,216,
%T 218,235,239,248,250,265,285,289,309,313,319,325,329,507,553,578,612,
%U 624,716,963,1037,1058,1147,1257,1406,1851,1887,1948,1961,2038,2196
%N Numbers k such that k + sigma(k) + phi(k) is a palindrome.
%H Robert Israel, <a href="/A116032/b116032.txt">Table of n, a(n) for n = 1..10000</a>
%e 1037 + sigma(1037) + phi(1037) = 3113.
%p ispali:= proc(n) local L,i;
%p L:= convert(n,base,10);
%p andmap(t -> L[t] = L[-t], [$1..nops(L)/2]);
%p end proc:
%p select(n -> ispali(n + numtheory:-sigma(n) + numtheory:-phi(n)), [$1..10000]); # _Robert Israel_, Dec 20 2023
%K nonn,base
%O 1,2
%A _Giovanni Resta_, Feb 13 2006