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.

A385261 Decimal expansion of the surface area of a gyroelongated pentagonal bicupola with unit edge.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jun 27 2025

Keywords

Comments

The gyroelongated pentagonal bicupola is Johnson solid J_46.

Examples

			26.431335857944513546973871516071261950885787743598...

Links

Crossrefs

Cf. A385260 (volume).
Cf. A002163, A002194, A384284, A385257, A385259.

Programs

  • Mathematica
    First[RealDigits[(20 + 15*Sqrt[3] + Sqrt[25 + 10*Sqrt[5]])/2, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J46", "SurfaceArea"], 10, 100]]

Formula

Equals (20 + 15*sqrt(3) + sqrt(25 + 10*sqrt(5)))/2 = (20 + 15*A002194 + sqrt(25 + 10*A002163))/2.
Equals the largest root of x^8 - 80*x^7 + 2100*x^6 - 14000*x^5 - 174750*x^4 + 1390000*x^3 + 9603125*x^2 + 9937500*x - 6546875.

A385262 Decimal expansion of the volume of a gyroelongated pentagonal cupolarotunda with unit edge.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jun 27 2025

Keywords

Comments

The gyroelongated pentagonal cupolarotunda is Johnson solid J_47.

Examples

			15.991096162004890063062980011720804055694009940053...

Links

Crossrefs

Cf. A385263 (surface area).
Cf. A002163, A384283, A385256, A385258, A385260.

Programs

  • Mathematica
    First[RealDigits[5/12*(11 + 5*# + 2*Sqrt[2*(Sqrt[650 + 290*#] - # - 1)]) & [Sqrt[5]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J47", "Volume"], 10, 100]]

Formula

Equals (5/12)*(11 + 5*sqrt(5) + 2*sqrt(2*(sqrt(650 + 290*sqrt(5)) - sqrt(5) - 1))) = (5/12)*(11 + 5*A002163 + 2*sqrt(2*(sqrt(650 + 290*A002163) - A002163 - 1))).
Equals the largest real root of 1679616*x^8 - 61585920*x^7 + 851472000*x^6 - 5108832000*x^5 + 4745790000*x^4 + 21346200000*x^3 - 29019375000*x^2 - 4576875000*x - 405859375.

A385264 Decimal expansion of the volume of a gyroelongated pentagonal birotunda with unit edge.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jun 30 2025

Keywords

Comments

The gyroelongated pentagonal birotunda is Johnson solid J_48.

Examples

			20.5848138117963990020365269299359278989411403764...

Links

Crossrefs

Cf. A385488 (surface area).
Cf. A002163, A384283, A385260, A385262.

Programs

  • Mathematica
    First[RealDigits[(45 + 17*# + 5*Sqrt[2*(Sqrt[650 + 290*#] - # - 1)])/6 & [Sqrt[5]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J48", "Volume"], 10, 100]]

Formula

Equals (45 + 17*sqrt(5) + 5*sqrt(2*(sqrt(650 + 290*sqrt(5)) - sqrt(5) - 1)))/6 = (45 + 17*A002163 + 5*sqrt(2*(sqrt(650 + 290*A002163) - A002163 - 1)))/6.
Equals the largest real root of 6561*x^8 - 393660*x^7 + 9316620*x^6 - 108207900*x^5 + 601832025*x^4 - 1417189500*x^3 + 965841750*x^2 + 597667500*x - 668786875.
Showing 1-3 of 3 results.

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

Content is available under The OEIS End-User License Agreement.