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 1-4 of 4 results.

A020771 Decimal expansion of 1/sqrt(14).

Original entry on oeis.org

2, 6, 7, 2, 6, 1, 2, 4, 1, 9, 1, 2, 4, 2, 4, 3, 8, 4, 6, 8, 4, 5, 5, 3, 4, 8, 0, 8, 7, 9, 7, 5, 3, 5, 2, 1, 5, 5, 4, 0, 0, 1, 4, 1, 4, 8, 4, 1, 3, 3, 7, 6, 3, 9, 0, 2, 1, 6, 9, 6, 1, 0, 4, 8, 0, 8, 5, 7, 3, 9, 3, 9, 7, 3, 6, 2, 0, 9, 9, 3, 0, 5, 6, 9, 7, 7, 2, 1, 3, 5, 3, 7, 1, 0, 2, 7, 1, 1, 2
Offset: 0

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Author

N. J. A. Sloane

Keywords

Comments

1/sqrt(14) = 0.267261241912424384684553480879753521554001414841337639021696104808573939736... [Vladimir Joseph Stephan Orlovsky, May 30 2010]

Links

Programs

Formula

Equals 1/A010471 = A010503 * A020764. - R. J. Mathar, Nov 19 2024

A020799 Decimal expansion of 1/sqrt(42).

Original entry on oeis.org

1, 5, 4, 3, 0, 3, 3, 4, 9, 9, 6, 2, 0, 9, 1, 9, 1, 0, 2, 6, 1, 0, 9, 4, 4, 6, 2, 7, 6, 3, 9, 9, 9, 9, 2, 0, 4, 2, 1, 5, 5, 2, 4, 8, 3, 5, 0, 1, 3, 8, 9, 2, 0, 3, 5, 6, 4, 5, 5, 6, 0, 5, 7, 0, 9, 0, 7, 0, 5, 1, 7, 5, 6, 6, 2, 9, 5, 3, 4, 3, 7, 4, 1, 4, 2, 9, 4, 3, 0, 7, 3, 0, 0, 1, 3, 3, 5, 7, 7
Offset: 0

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Author

N. J. A. Sloane

Keywords

Comments

1/sqrt(42) = 0.154303349962091910261094462763999920421552483501389203564556057090705175663... [Vladimir Joseph Stephan Orlovsky, Jun 01 2010]

Links

Programs

Formula

Equals A020763 * A020764 . - R. J. Mathar, Nov 14 2023

A229977 Gosper island perimeter (rounded to the nearest integer) after n iterations, let starting perimeter = 1.

Original entry on oeis.org

1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 4, 5, 5, 6, 7, 7, 8, 10, 11, 12, 14, 16, 18, 20, 23, 26, 30, 34, 38, 43, 49, 56, 63, 72, 81, 92, 105, 119, 134, 152, 173, 196, 222, 252, 286, 324, 367, 416, 472, 535, 607, 688, 780, 885, 1003
Offset: 0

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Author

Kival Ngaokrajang, Oct 05 2013

Keywords

Comments

The Gosper island curve bounds the space filled by the Peano-Gosper curve. The length of Peano-Gosper curve after n iterations (rounded to the nearest integer) is A017926(n) and the total number of elements is A000420(n). See illustration in links.
The sequence expansion ratio (a(n)/a(n-1)) is 1.133893419... which is 3*A020764.

Links

Crossrefs

Cf. A017926, A000420, A227381 (Koch snowflake perimeter).

Formula

a(n) = round((3/sqrt(7))^n).

A171536 Decimal expansion of 2/sqrt(7).

Original entry on oeis.org

7, 5, 5, 9, 2, 8, 9, 4, 6, 0, 1, 8, 4, 5, 4, 4, 5, 4, 4, 2, 9, 0, 3, 3, 0, 7, 2, 4, 6, 8, 3, 6, 0, 1, 2, 1, 6, 3, 1, 5, 0, 2, 6, 2, 3, 7, 3, 7, 8, 4, 2, 9, 0, 8, 6, 7, 6, 6, 6, 6, 9, 8, 8, 3, 4, 3, 1, 6, 2, 5, 2, 0, 9, 2, 2, 9, 3, 8, 1, 7, 9, 3, 6, 0, 1, 1, 2, 2, 5, 3, 2, 7, 8, 4, 4, 1, 0, 3, 1, 6, 0, 4, 3, 0, 4
Offset: 0

Views

Author

R. J. Mathar, Dec 11 2009

Keywords

Comments

The absolute value of the Clebsch-Gordan coupling coefficient = <2 3/2 ; -2 -1/2 | 5/2 -5/2>.

Examples

			sqrt(4/7) = 0.75592894601845445442903307...

Links

Programs

  • Mathematica
    RealDigits[2/Sqrt[7],10,120][[1]] (* Harvey P. Dale, Jan 02 2022 *)

Formula

equals 2*A020764 = 2/A010465.
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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