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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A050223 Digit sums of hoax numbers A019506.

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%I A050223 #22 Feb 16 2025 08:32:40
%S A050223 4,13,12,13,13,10,7,13,4,9,7,13,13,11,13,12,13,13,10,13,13,13,10,15,
%T A050223 13,15,17,15,12,13,13,13,13,15,13,14,15,11,15,12,15,15,9,13,12,15,15,
%U A050223 22,18,14,15,22,13,15,13,21,22,22,15,4,9,14,13,13,13,13,7,12,9,17,13
%N A050223 Digit sums of hoax numbers A019506.
%H A050223 Reinhard Zumkeller, <a href="/A050223/b050223.txt">Table of n, a(n) for n = 1..10000</a>
%H A050223 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HoaxNumber.html">Hoax Number</a>.
%F A050223 a(n) = A007953(A019506(n)).
%o A050223 (PARI) ishoax(m) = !isprime(m) && (sumdigits(m) == vecsum(apply(sumdigits, factor(m)[, 1]))); \\ A019506
%o A050223 lista(nn) = apply(sumdigits, select(ishoax, [1..nn])); \\ _Michel Marcus_, Feb 24 2023
%Y A050223 Cf. A007953, A019506.
%Y A050223 Cf. A202393, A050218.
%K A050223 nonn,base
%O A050223 1,1
%A A050223 _Eric W. Weisstein_