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Lesser of twin primes of the form 6*Fibonacci(k)-1.
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%I #40 Feb 07 2019 12:55:42

%S 5,11,17,29,278207,63661259146337

%N Lesser of twin primes of the form 6*Fibonacci(k)-1.

%C Corresponding values for k are 1 or 2, 3, 4, 5, 24, 64, ... Also a(7), if it exists, exceeds 6*Fibonacci(150000).

%e 17 = 6*Fibonacci(4) - 1 = 6*3 - 1.

%o (PARI)

%o for (n=2, 1000, if (ispseudoprime (p=6*fibonacci(n)-1) && ispseudoprime (p+2), print1(p", ")))

%Y Cf. A001359 (lesser of twin primes).

%K nonn,more

%O 1,1

%A _Gilbert Mozzo_, Jan 12 2019