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A120934 Least prime p such that the interval [p,p+log(p)] contains n primes. +0
3
2, 11, 457, 3251, 165701, 10526557, 495233351, 196039655873, 10687033762033, 79006533276941, 4313367040646743 (list; graph; listen)
OFFSET

1,1

COMMENT

Soundararajan states that, on average, there is one prime in the interval [k,k+log(k)] for any number k. Is there an upper limit to the number of primes in such an interval?Not if the prime k-tuple conjecture is true, in which case a(n) exists for all n. Note that a(n) > e^A008407(n). See A120935 for the largest prime in the interval.

LINKS

K. Soundararajan, The distribution of prime numbers

Eric Weisstein's World of Mathematics, Prime k-Tuple Conjecture

EXAMPLE

a(2)=11 because p=11 is the first prime with log(p)>2 and 11+2 is prime.

MATHEMATICA

i=1; Table[While[p=Prime[i]; PrimePi[p+Log[p]]-PrimePi[p]+1< n, i++ ]; p, {n, 5}]

CROSSREFS

Cf. A120936 (number of primes in the interval [n, n+log(n)]).

Sequence in context: A012950 A012979 A013109 this_sequence A000886 A128855 A157033

Adjacent sequences: A120931 A120932 A120933 this_sequence A120935 A120936 A120937

KEYWORD

hard,nonn

AUTHOR

T. D. Noe (noe(AT)sspectra.com), Jul 21 2006

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Last modified December 16 17:18 EST 2009. Contains 170825 sequences.


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