A215051 Number of primes of the form 1 + b^32 for 1 < b < 10^n.
0, 3, 22, 146, 1062, 8963, 74951, 651537, 5740807, 51389252
Offset: 1
Examples
a(2) = 3 because the Fermat numbers F_5(b) where b<10^2 are prime only for b = 30, 54, 96.
Links
Programs
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Mathematica
Table[Length[Select[Range[2,10^n-1]^32 + 1, PrimeQ]], {n, 4}] (* T. D. Noe, Aug 01 2012 *) -
PARI
a(n) = sum(b=1, 10^n/2-1, isprime((2*b)^32+1))
Formula
a(n) = A214956(32*n) - 1.
Extensions
a(9)-a(10) from Chai Wah Wu, Oct 18 2018
Comments