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A116032
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Numbers k such that k + sigma(k) + phi(k) is a palindrome.
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1
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1, 2, 3, 11, 12, 14, 16, 32, 33, 37, 47, 76, 101, 108, 126, 131, 134, 144, 168, 188, 216, 218, 235, 239, 248, 250, 265, 285, 289, 309, 313, 319, 325, 329, 507, 553, 578, 612, 624, 716, 963, 1037, 1058, 1147, 1257, 1406, 1851, 1887, 1948, 1961, 2038, 2196
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OFFSET
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1,2
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LINKS
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EXAMPLE
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1037 + sigma(1037) + phi(1037) = 3113.
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MAPLE
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ispali:= proc(n) local L, i;
L:= convert(n, base, 10);
andmap(t -> L[t] = L[-t], [$1..nops(L)/2]);
end proc:
select(n -> ispali(n + numtheory:-sigma(n) + numtheory:-phi(n)), [$1..10000]); # Robert Israel, Dec 20 2023
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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