%I #10 Apr 03 2023 10:36:12
%S 3,4,5,10,14,17,18,19,25,27,30,33,34,38,44,49,52,54,55,59,63,67,69,70,
%T 72,80,89,94,97,98,102,103,104,105,107,110,128,130,132,135,140,149,
%U 154,157,158,163,174,175,177,185,187,188,199,203,220,223,224,228,237,238,240,245,249,257,258,262,265,268,270,279,280,287,290,292
%N Numbers k such that 666k-1 is prime.
%H C. Caldwell, <a href="https://t5k.org/primes/page.php?id=101882">139ยท666^178851 - 1</a>, Sep 08 2011
%e a(1)=3 since 3*666-1 = 1997 = A063472(1) is prime, and the smallest prime to be of that form.
%e K=139*666^178850 is also a member of this sequence, since 139*666^178851-1 is prime (cf. link).
%o (PARI) for(k=1,999,ispseudoprime(k*666-1)&print1(k","))
%Y Cf. A063472, A037029, A037030.
%K nonn
%O 1,1
%A _M. F. Hasler_, Sep 09 2011