%I #29 Aug 22 2022 10:08:50
%S 2,3,7,17,59,283,311,383,499,521,541,599,1193,1993,2671,7547,24019,
%T 46301,48121,68597,91283,131497,148663,184463,341233
%N Numbers k such that 4^k - 3^k is prime.
%C Some of the larger entries may only correspond to probable primes.
%C The values corresponding to 1193 (719 digits) and 1993 (1200 digits) have been certified prime with Primo. - _Rick L. Shepherd_, Sep 10 2002
%C 8 more terms found by Jean-Louis Charton during 2004 - 2006. Corresponding numbers of decimal digits are 14461, 27876, 28972, 41300, 54958, 79170, 89505, 111058, 205443. - _Alexander Adamchuk_, Dec 02 2006
%H Bogley, William A.; Williams, <a href="https://doi.org/10.1007/s00209-016-1664-3">Gerald Efficient finite groups arising in the study of relative asphericity</a>. Math. Z. 284, No. 1-2, 507-535 (2016).
%t Select[Range[1000], PrimeQ[4^# - 3^#] &] (* _Alonso del Arte_, Nov 03 2011 *)
%o (PARI) select(vector(10^5,i,i),n->ispseudoprime(4^n-3^n)) \\ _Charles R Greathouse IV_, Feb 11 2011
%Y Cf. A000043, A057468, A059802, etc., A129736, A129737.
%K nonn,nice,hard
%O 1,1
%A _Mike Oakes_, Feb 23 2001