%I #23 Feb 06 2021 22:09:16
%S 13,15,19,23,31,33,35,37,43,47,51,52,59,73,78,85,93,94,97,99,105,106,
%T 109,113,115,119,127,129,139,141,149,159,163,165,168,169,179,181,189,
%U 199,211,213,218,231,232,237,245,251,256,258,259,271,273,274,275,294,301,303,304,307,339,344,347,348
%N Numbers k such that A316650(k) is prime.
%H Robert Israel, <a href="/A340618/b340618.txt">Table of n, a(n) for n = 1..10000</a>
%e a(4) = 23 is a term because A316650(23) = 43 is prime.
%p f:= proc(n) local a,b,c;
%p c:= convert(convert(n,base,10),`+`);
%p a:= floor(n/c);
%p b:= n mod c;
%p 10^(1+ilog10(b))*a+b;
%p end proc:
%p select(n -> isprime(f(n)), [$1..100]);
%Y Cf. A316650.
%K nonn,base
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Jan 15 2021
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