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 1-5 of 5 results.

A380735 Decimal expansion of the long/short edge length ratio of a disdyakis dodecahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jan 31 2025

Keywords

Comments

Apart from leading digits the same as A343069. - R. J. Mathar, Feb 03 2025

Examples

			1.630601937481870721257384103458528296938524553625...

Links

Crossrefs

Cf. A380734 (medium/short edge length ratio).
Cf. A002193, A378393, A378712, A378713, A378714, A378715, A380736, A380737, A380738.

Programs

  • Mathematica
    First[RealDigits[(10 + Sqrt[2])/7, 10, 100]]
  • PARI
    (10 + sqrt(2))/7 \\ Charles R Greathouse IV, Feb 05 2025

Formula

Equals (10 + sqrt(2))/7 = (10 + A002193)/7.

A344520 Decimal expansion of 2*(1+sqrt(10))/3.

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 22 2021

Keywords

Comments

Trisect the unit square into 3 regions with equal areas from a given midpoint on the squares edge. This sequence gives the decimal expansion of the perimeter of the triangular region.

Examples

			2.7748517734455862213325956962884790...

Crossrefs

Similar sequences into k regions: A344554 (k=5), A343069 (k=7), A344568 (k=9), A344569 (k=17).

Programs

  • Mathematica
    RealDigits[2 (1 + Sqrt[10])/3, 10, 200][[1]] // Flatten

Formula

Decimal expansion of 2*(1 + k*sqrt(1/k^2 + 1))/k, where k = 3.

A344554 Decimal expansion of 2*(1+sqrt(26))/5.

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 23 2021

Keywords

Comments

Dissect the unit square into 5 regions with equal areas from a given midpoint on the squares edge. This sequence gives the decimal expansion of the perimeter of the triangular region with unit height.

Examples

			2.43960780543711393201128964360...

Crossrefs

Similar sequences into k regions: A344520 (k=3), A343069 (k=7), A344568 (k=9), A344569 (k=17).

Programs

  • Mathematica
    RealDigits[2 (1 + Sqrt[26])/5, 10, 200][[1]] // Flatten

Formula

Decimal expansion of 2*(1 + k*sqrt(1/k^2 + 1))/k, where k = 5.

A344568 Decimal expansion of 2*(1+sqrt(82))/9.

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 23 2021

Keywords

Comments

Dissect the unit square into 9 regions with equal areas from a given midpoint on the squares edge. This sequence gives the decimal expansion of the perimeter of the triangular region with unit height.

Examples

			2.2345300306972036947941795926631...

Crossrefs

Similar sequences into k regions: A344520 (k=3), A344554 (k=5), A343069 (k=7), A344569 (k=17).

Programs

  • Mathematica
    RealDigits[2 (1 + Sqrt[82])/9, 10, 200][[1]] // Flatten

Formula

Decimal expansion of 2*(1 + k*sqrt(1/k^2 + 1))/k, where k = 9.

A344569 Decimal expansion of 2*(1+sqrt(290))/17.

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 23 2021

Keywords

Comments

Dissect the unit square into 17 regions with equal areas from a given midpoint on the squares edge. This sequence gives the decimal expansion of the perimeter of the triangular region with unit height.

Examples

			2.121104278344282490133331979...

Crossrefs

Similar sequences into k regions: A344520 (k=3), A344554 (k=5), A343069 (k=7), A344568 (k=9).

Programs

  • Mathematica
    RealDigits[2 (1 + Sqrt[290])/17, 10, 200][[1]] // Flatten

Formula

Decimal expansion of 2*(1 + k*sqrt(1/k^2 + 1))/k, where k = 17.
Showing 1-5 of 5 results.

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