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 A272272 Numbers k such that 4^k-3^(k+1) is prime. 0
 4, 8, 24, 36, 48, 246, 608, 734, 774, 824, 9348, 1244, 3230, 4656, 5448, 6360, 7598, 15390, 48158, 86754 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(21) > 10^5. LINKS EXAMPLE 8 is a member since 4^8 - 3^9 = 65536-19683 = 45853 which is a prime number. MATHEMATICA Select[Range[4, 100000], PrimeQ[4^# - 3^(# + 1)] &] PROG (PARI) lista(nn) = for(n=1, nn, if(ispseudoprime(4^n-3^(n+1)), print1(n, ", "))); \\ Altug Alkan, Apr 24 2016 CROSSREFS Cf. A093713, A082103, A093717, A093793, A096185, A093794, A093795, A096186, A271883. Sequence in context: A212019 A075708 A066617 * A024589 A062015 A006640 Adjacent sequences:  A272269 A272270 A272271 * A272273 A272274 A272275 KEYWORD nonn,more AUTHOR Robert Price, Apr 24 2016 STATUS approved

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Last modified January 17 11:27 EST 2022. Contains 350394 sequences. (Running on oeis4.)