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A110068
Numbers n such that 10^(n-1) + pi(n) is the smallest n-digit prime.
2
2, 6, 23, 78, 5997
OFFSET
1,1
COMMENTS
In the Cramer model, the chance that there are no primes between 10^(n-1) and 10^(n-1) + pi(n) is 1 + o(1). The same heuristic suggests that there are infinitely many terms since the harmonic series diverges. [Charles R Greathouse IV, Nov 15 2010]
a(6) > 219035. - Robert Price, May 29 2015
PROG
(Python)
from sympy import nextprime, primepi
A110068_list = [n for n in range(1, 100) if nextprime(10**(n-1))-10**(n-1) == primepi(n)] # Chai Wah Wu, Apr 29 2018
CROSSREFS
Cf. A110065.
Sequence in context: A290954 A220213 A217200 * A247211 A150275 A335537
KEYWORD
nonn,base,more
AUTHOR
Farideh Firoozbakht, Jul 13 2005
EXTENSIONS
a(5) from Charles R Greathouse IV, Nov 15 2010
STATUS
approved