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.

A136295 Multiples of 100 which begin a span of 100 composite numbers.

Original entry on oeis.org

1671800, 2637800, 3117300, 3933600, 4640600, 4652400, 5178200, 5518700, 5837400, 5845200, 6012900, 6085000, 6333800, 6376200, 6789800, 6958700, 7129900, 7565200, 7803500, 7826900, 8027700, 8367400, 8421300, 8905200
Offset: 1

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Author

Julien Peter Benney (jpbenney(AT)gmail.com), Mar 21 2008

Keywords

Comments

As numbers become large, the proportion of centuries with no primes increases according to the prime number theorem.

Examples

			a(2) = 2637800 because there is a prime gap of 112 from 2637799 to 2637911, which makes the century from 2637800 to 2637899 the second one consisting wholly of composite numbers.
		

References

  • J. W. L. Glaisher, Factor table for the sixth million : containing the least factor of every number not divisible by 2,3, or 5 between 5,000,000 and 6,000,000; Taylor and Francis, 1883
  • J. Murray, Report of the Annual Meeting, British Association for the Advancement of Science, Vol. 50 (1881), p. 308.

Crossrefs

Programs

  • Mathematica
    100SequencePosition[PrimePi[100Range[90000]],{x_,x_}][[All,1]] (* Harvey P. Dale, Aug 19 2021 *)

Formula

a(n) ~ n. [Charles R Greathouse IV, Aug 21 2011]

Extensions

Definition clarified by Don Reble, Sep 06 2008