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%I #28 Jul 08 2021 03:10:38
%S 5,12,20,23,30,32,38,39,57,62,65,66,72,108,117,120,123,141,143,144,
%T 170,176,194,198,207,215,221,225,240,255,269,293,297,305,309,320,321,
%U 324,426,446,458,471,480,488,512,521,540,551,557,566,569,570,573,594,599
%N Numbers k such that the string k235711131719 is prime.
%C Also numbers k such that (10^12*k + 235711131719) is prime. - _Stefan Steinerberger_, Feb 15 2006
%H Daniel Starodubtsev, <a href="/A099192/b099192.txt">Table of n, a(n) for n = 1..10000</a>
%e If k = 5, then k235711131719 = 5235711131719 (prime).
%e If k = 38, then k235711131719 = 38235711131719 (prime).
%e If k = 72, then k235711131719 = 72235711131719 (prime).
%p q:= n-> isprime(parse(cat(n, 235711131719))):
%p select(q, [$1..1000])[]; # _Alois P. Heinz_, May 12 2021
%t For[n = 1, n < 500, n++, If[PrimeQ[10^12*n + 235711131719], Print[n]]] (* _Stefan Steinerberger_, Feb 15 2006 *)
%o (PARI) ok(n)={isprime(n*10^12+235711131719)} \\ _Andrew Howroyd_, Jan 23 2020
%o (Python)
%o from sympy import isprime
%o def aupto(limit):
%o alst = []
%o for k in range(1, limit+1):
%o if isprime(10**12*k + 235711131719): alst.append(k)
%o return alst
%o print(aupto(500)) # _Michael S. Branicky_, May 12 2021
%K base,nonn
%O 1,1
%A _Parthasarathy Nambi_, Mar 23 2005
%E More terms from _Stefan Steinerberger_, Feb 15 2006
%E a(17) corrected by _Daniel Starodubtsev_, Jan 22 2020
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