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.

A064025 Length of period of the continued fraction for sqrt(n!).

Original entry on oeis.org

1, 2, 2, 2, 4, 2, 16, 48, 8, 4, 56, 180, 44, 156, 300, 7936, 10388, 11516, 9104, 13469268, 2684084, 2418800, 28468692, 143007944, 85509116, 402570696, 2287868888, 204306960, 48715166536, 147160740856, 317585614148
Offset: 2

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Author

Labos Elemer, Sep 18 2001

Keywords

Examples

			Quotients for 10! are [[1904], [1, 15, 1, 13, 1, 15, 1, 3808]], so period length of 10! is 8.
		

Crossrefs

Programs

  • Maple
    with(numtheory): [seq(nops(cfrac(sqrt(k!),'periodic','quotients')[2]),k=2..16)];
  • Mathematica
    Do[ Print[ Length[ Last[ ContinuedFraction[ Sqrt[ n! ]]]]], {n, 2, 24} ]

Formula

a(n) = A003285(A000142(n)). - Michel Marcus, Sep 25 2019

Extensions

More terms from Robert G. Wilson v, Oct 01 2001
a(25)-a(28) from Daniel Suteu, Jan 24 2019
a(29) from Chai Wah Wu, Sep 23 2019
a(30) from Chai Wah Wu, Sep 25 2019
a(31) from Chai Wah Wu, Jan 27 2021
a(32) from Chai Wah Wu, Feb 02 2021