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 1-3 of 3 results.

A075357 a(n) = smallest k such that (n+1)(n+2)...(n+k) >= n!.

Original entry on oeis.org

0, 1, 2, 2, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 10, 11, 11, 12, 13, 13, 14, 15, 16, 16, 17, 18, 18, 19, 20, 21, 21, 22, 23, 24, 24, 25, 26, 27, 27, 28, 29, 30, 30, 31, 32, 33, 33, 34, 35, 36, 37, 37, 38, 39, 40, 40, 41, 42, 43, 43, 44, 45, 46, 47, 47, 48, 49, 50, 50, 51, 52, 53, 53, 54
Offset: 1

Views

Author

Amarnath Murthy, Sep 19 2002

Keywords

Comments

Is this sequence the same as A094331? - David Wasserman, Jan 16 2005

Crossrefs

Cf. A075358.
Cf. A094331.

Programs

  • PARI
    a(n) = my(k=0); while ((n+k)! < n!^2, k++); k; \\ Michel Marcus, Apr 11 2022
    
  • Python
    from math import factorial
    def a(n):
        if n == 1: return 0
        fn, k, p = factorial(n), 1, n+1
        while fn > p: k += 1; p *= (n+k)
        return k
    print([a(n) for n in range(1, 75)]) # Michael S. Branicky, Apr 11 2022

Extensions

More terms from David Wasserman, Jan 16 2005

A213854 Least m>0 such that m!*3^m >= n!.

Original entry on oeis.org

1, 1, 2, 3, 3, 4, 5, 6, 6, 7, 8, 9, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 17, 18, 19, 20, 21, 21, 22, 23, 24, 25, 25, 26, 27, 28, 29, 29, 30, 31, 32, 33, 34, 34, 35, 36, 37, 38, 38, 39, 40, 41, 42, 43, 43, 44, 45, 46, 47, 48, 48, 49, 50
Offset: 1

Views

Author

Clark Kimberling, Jul 17 2012

Keywords

Examples

			a(6) = 4 because 3^3*3! < 6! <= 3^4*4!.
		

Crossrefs

Programs

A213851 Least m such that m!*2^m >= n!

Original entry on oeis.org

1, 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 18, 19, 20, 21, 22, 23, 24, 24, 25, 26, 27, 28, 29, 30, 31, 31, 32, 33, 34, 35, 36, 37, 38, 38, 39, 40, 41, 42, 43, 44, 45, 46, 46, 47, 48, 49, 50, 51, 52, 53, 53, 54
Offset: 1

Views

Author

Clark Kimberling, Jul 17 2012

Keywords

Examples

			a(8) = 6 because (2^5)*5! < 8! <= (2^6)*6!.
		

Crossrefs

Cf. A094331.

Programs

  • Mathematica
    Table[m=1; While[n!>(2^m)*m!, m++]; m, {n,1,100}]
Showing 1-3 of 3 results.