cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A120935 Largest prime in the cluster of n primes whose first prime is given in A120934.

Original entry on oeis.org

2, 13, 463, 3259, 165713, 10526573, 495233371, 196039655899, 10687033762063, 79006533276973, 4313367040646779, 1740318019946551973
Offset: 1

Views

Author

T. D. Noe, Jul 21 2006

Keywords

Comments

For n>1, it appears that each prime is a cluster prime. See A038134.

Crossrefs

Cf. A020497.

Formula

a(n)= A120934(n)+A008407(n)

Extensions

a(12) from Donovan Johnson, Apr 18 2012

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

Original entry on oeis.org

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

Views

Author

T. D. Noe, Jul 21 2006

Keywords

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.

Crossrefs

Programs

  • Mathematica
    Table[Length[Select[Range[n,n+Log[n]],PrimeQ]], {n,150}]
  • PARI
    a(n)=sum(k=n,n+log(n),isprime(k)) \\ Charles R Greathouse IV, Apr 17 2012
Showing 1-2 of 2 results.