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A214956
Number of primes of the form x^32 + 1 less than 10^n.
2
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 6, 6, 7, 7, 7, 8, 8, 8, 8, 8
OFFSET
1,48
COMMENTS
It is conjectured that there are infinitely many primes of the form x^32 + 1 (and thus this sequence never becomes constant), but this has not been proved.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..304 (n = 1..128 from Henryk Dabrowski)
EXAMPLE
a(55) = 2 because the only primes of the form x^32 + 1 < 10^55 are the primes: 2, 185302018885184100000000000000000000000000000001.
PROG
(PARI) a(n) = sum(k=1, (10^n-1)^(1/32), isprime(k^32+1))
CROSSREFS
Cf. A006315 (k such that k^32+1 is prime).
Sequence in context: A261226 A003108 A279223 * A209899 A111898 A279041
KEYWORD
nonn
AUTHOR
Henryk Dabrowski, Jul 30 2012
STATUS
approved