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A120936
Number of primes in the interval [n,n+log(n)].
3
0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 2, 1, 1, 0, 1, 1, 2, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 2, 2, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 2, 2, 2, 1, 1, 0, 1, 1, 1, 1, 2, 1, 2, 2, 2, 1, 1, 0, 1, 1, 1, 1, 2, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2
OFFSET
1,11
COMMENTS
Soundararajan states that, on average, there is one prime in the interval [n,n+log(n)] for any number n. See A120934 for the prime n that yield new records.
MATHEMATICA
Table[Length[Select[Range[n, n+Log[n]], PrimeQ]], {n, 150}]
PROG
(PARI) a(n)=sum(k=n, n+log(n), isprime(k)) \\ Charles R Greathouse IV, Apr 17 2012
CROSSREFS
Sequence in context: A037906 A319394 A278347 * A335294 A214438 A173432
KEYWORD
nonn
AUTHOR
T. D. Noe, Jul 21 2006
STATUS
approved