A215970 Number of primes of the form 1 + b^65536 for 1 < b < 10^n.
0, 0, 0, 0, 1, 14, 28
Offset: 1
Keywords
Examples
a(5) = 1 because the generalized Fermat numbers F_16(b) where b<10^5 are prime only for b = 48594.
Links
- Yves Gallot, Status of the smallest base values yielding Generalized Fermat primes
- Yves Gallot, How many prime numbers appear in a sequence ?
- Yves Gallot, A Problem on the Conjecture Concerning the Distribution of Generalized Fermat Prime numbers (a new method for the search for large primes)
- Mersenne Wiki, Table of known GF primes b^n+1 where n (exponent) is at least 8192
Crossrefs
Programs
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PARI
a(n) = sum(b=1, 10^n/2-1, isprime((2*b)^65536+1))
Comments