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.

Previous Showing 21-25 of 25 results.

A352672 Decimal expansion of r = (3/2)*(1+sqrt(3)).

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Mar 26 2022

Keywords

Examples

			4.098076211353315940291169512258808550414...
		

Crossrefs

Apart from leading digits the same as A176325 and A104956.

Programs

  • Mathematica
    r = N[(3/2) (1 + Sqrt[3]), 200]
    RealDigits[r][[1]]

Formula

Equals A104956 + 3/2. - Michel Marcus, Mar 28 2022
Equals (3/2) * A090388. - Bernard Schott, Mar 28 2022

A337301 Triangle read by rows in which row n lists the closest integers to diagonal lengths of regular n-gon with unit edge length, n >= 4.

Original entry on oeis.org

1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 3, 3, 3, 2, 2, 3, 3, 3, 3, 3, 2, 2, 3, 3, 4, 4, 3, 3, 2, 2, 3, 3, 4, 4, 4, 3, 3, 2, 2, 3, 3, 4, 4, 4, 4, 3, 3, 2, 2, 3, 4, 4, 4, 4, 4, 4, 4, 3, 2, 2, 3, 4, 4, 5, 5, 5, 5, 4, 4, 3, 2, 2, 3, 4, 4, 5, 5, 5, 5, 5, 4, 4, 3, 2
Offset: 4

Views

Author

Mohammed Yaseen, Aug 22 2020

Keywords

Examples

			Triangle begins:
1;
2, 2;
2, 2, 2;
2, 2, 2, 2;
2, 2, 3, 2, 2;
2, 3, 3, 3, 3, 2;
2, 3, 3, 3, 3, 3, 2;
2, 3, 3, 4, 4, 3, 3, 2;
2, 3, 3, 4, 4, 4, 3, 3, 2;
2, 3, 3, 4, 4, 4, 4, 3, 3, 2;
2, 3, 4, 4, 4, 4, 4, 4, 4, 3, 2;
2, 3, 4, 4, 5, 5, 5, 5, 4, 4, 3, 2;
2, 3, 4, 4, 5, 5, 5, 5, 5, 4, 4, 3, 2;
...
Row n lists the closest integers to the length of the diagonals drawn from a fixed vertex of a regular n-gon with unit edge length, n >= 4.
The lengths of the diagonals drawn from vertex A of a regular 8-gon ABCDEFGH with unit edge length are:
AC = 1.84775...
AD = 2.41421...
AE = 2.61312...
AF = 2.41421...
AG = 1.84775...
So the row for n=8 is 2, 2, 3, 2, 2.
		

Crossrefs

Cf. A064313.
Decimal expansion of diagonal lengths of regular n-gons with unit edge length:
n=4 A002193.
n=5 A001622.
n=9 A332437.
n=11 A231186.

Programs

  • Mathematica
    T[n_,k_]:=Round[Sin[(k+1)*Pi/n]/Sin[Pi/n]]; Flatten[Table[T[n,k],{n,4,16},{k,1,n-3}]] (* Stefano Spezia, Sep 07 2020 *)

Formula

T(n,k) = round(sin((k+1)*Pi/n)/sin(Pi/n)), n >= 4, 1 <= k <= n-3.

A343620 Decimal expansion of the Hausdorff dimension of 4 X 2 carpets with rows of 3 and 1 sub-parts.

Original entry on oeis.org

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

Views

Author

Kevin Ryde, Aug 04 2021

Keywords

Comments

Bedford (page 100 figure 34) gives this type of carpet as an example where the Hausdorff dimension differs from the capacity dimension (which is 3/2).
+---+---+---+---+ Fractal carpet with each S
| | S | S | S | a shrunken copy of the whole.
+---+---+---+---+ Any 3 parts in one row and
| S | | | | 1 part in the other row.
+---+---+---+---+

Examples

			1.4499843134764958489211625600623791...
		

Crossrefs

Cf. A346639 (3 X 2 carpets), A090388 (1+sqrt(3)).

Programs

  • Mathematica
    RealDigits[Log2[1 + Sqrt[3]], 10, 100][[1]] (* Amiram Eldar, Aug 04 2021 *)

Formula

Equals log_2(1+sqrt(3)).

A344111 Decimal expansion of 4 + sqrt(3).

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 10 2021

Keywords

Comments

Decimal expansion of the surface area of a gyrobifastigium with regular faces and unit edge length.
Essentially the same sequence of digits as A176102, A165663, A160390, A090388, A019973 and A002194. - R. J. Mathar, May 16 2021

Examples

			5.73205080756887729...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[4 + Sqrt[3], 10, 100] // Flatten

A379467 Decimal expansion of (1 + sqrt(3))/3.

Original entry on oeis.org

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

Views

Author

Stefano Spezia, Dec 23 2024

Keywords

Examples

			0.91068360252295909784248211383529078898093508460346...
		

References

  • Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 8.6, p. 504.

Crossrefs

Programs

  • Mathematica
    RealDigits[(1+Sqrt[3])/3,10,100][[1]]

Formula

Equals A090388/3.
Minimal polynomial: 9*x^2 - 6*x - 2. - Stefano Spezia, Aug 03 2025
Previous Showing 21-25 of 25 results.