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%I #12 May 07 2022 15:28:25
%S 1,14,29,32,38,41,56,71,89,95,107,113,119,155,164,173,185,203,212,236,
%T 251,263,275,278,290,293,299,305,311,326,344,371,377,395,401,416,419,
%U 437,467,470,473,479,485,497,509,524,527,539,569,584,587,593,611,623,635,641,659,665,671,674,692,701
%N Numbers k such that k + s + k*s is prime, where s is the sum of digits of k.
%C Except for 1, all terms == 2 (mod 3).
%H Robert Israel, <a href="/A353197/b353197.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3) = 29 is a term because its sum of digits is 2+9 = 11 and 29 + 11 + 29*11 = 359 is prime.
%p f:= proc(n) local s,t;
%p s:= convert(convert(n,base,10),`+`);
%p n+s+s*n;
%p end proc:
%p select(t -> isprime(f(t)), [1,seq(i,i=2..10000,3)]);
%o (Python)
%o from sympy import isprime
%o def ok(n): s = sum(map(int, str(n))); return isprime(n + s + n*s)
%o print([k for k in range(702) if ok(k)]) # _Michael S. Branicky_, Apr 29 2022
%Y Cf. A007953.
%K nonn,base
%O 1,2
%A _Robert Israel_, Apr 29 2022
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