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 11-18 of 18 results.

A377298 Decimal expansion of the surface area of a truncated cube with unit edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Oct 25 2024

Keywords

Examples

			32.4346643636148951726751573735281216767216730121...
		

Crossrefs

Cf. A377299 (volume), A294968 (circumradius), A010503 (midradius - 1), A377296 (Dehn invariant, negated).

Programs

  • Mathematica
    First[RealDigits[2*(6 + Sqrt[72] + Sqrt[3]), 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["TruncatedCube", "SurfaceArea"], 10, 100]]

Formula

Equals 2*(6 + 6*sqrt(2) + sqrt(3)) = 2*(6 + 2*A002193 + A002194) = 12 + 2*A010524 + A010469.

A377345 Decimal expansion of the circumradius of a truncated cuboctahedron (great rhombicuboctahedron) with unit edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Oct 26 2024

Keywords

Examples

			2.3176109128927665137791474633402948053450518945...
		

Crossrefs

Cf. A377343 (surface area), A377344 (volume), A377346 (midradius).
Cf. A010524.

Programs

  • Mathematica
    First[RealDigits[Sqrt[13 + 6*Sqrt[2]]/2, 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["TruncatedCuboctahedron", "Circumradius"], 10, 100]]

Formula

Equals sqrt(13 + 6*sqrt(2))/2 = sqrt(13 + A010524)/2.

A377346 Decimal expansion of the midradius of a truncated cuboctahedron (great rhombicuboctahedron) with unit edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Oct 26 2024

Keywords

Examples

			2.26303343845371462359202580343253714222906720265...
		

Crossrefs

Cf. A377343 (surface area), A377344 (volume), A377345 (circumradius).
Cf. A010527 (analogous for a cuboctahedron).

Programs

  • Mathematica
    First[RealDigits[Sqrt[3 + 3/Sqrt[2]], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["TruncatedCuboctahedron", "Midradius"], 10, 100]]

Formula

Equals sqrt(12 + 6*sqrt(2))/2 = sqrt(12 + A010524)/2 = sqrt(3 + 3/sqrt(2)) = sqrt(3 + A230981).

A041126 Numerators of continued fraction convergents to sqrt(72).

Original entry on oeis.org

8, 17, 280, 577, 9512, 19601, 323128, 665857, 10976840, 22619537, 372889432, 768398401, 12667263848, 26102926097, 430314081400, 886731088897, 14618011503752, 30122754096401, 496582077046168, 1023286908188737, 16869172608065960, 34761632124320657
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[72], 30]] (* Vincenzo Librandi, Oct 29 2013 *)
    a0[n_] := (-4+3*Sqrt[2])*(17+12*Sqrt[2])^n-((4+3*Sqrt[2])/(17+12*Sqrt[2])^n) // Simplify
    a1[n_] := (1/(17+12*Sqrt[2])^n+(17+12*Sqrt[2])^n)/2 // FullSimplify
    Flatten[MapIndexed[{a0[#], a1[#]} &, Range[20]]] (* Gerry Martens, Jul 11 2015 *)

Formula

G.f.: -(x+1)*(x^2-9*x-8) / ((x^2-6*x+1)*(x^2+6*x+1)). - Colin Barker, Nov 05 2013
From Gerry Martens, Jul 11 2015: (Start)
Interspersion of 2 sequences [a1(n),a0(n)] for n>0:
a0(n) = (-4+3*sqrt(2))*(17+12*sqrt(2))^n-((4+3*sqrt(2))/(17+12*sqrt(2))^n).
a1(n) = (1/(17+12*sqrt(2))^n+(17+12*sqrt(2))^n)/2. (End)

Extensions

More terms from Colin Barker, Nov 05 2013

A041127 Denominators of continued fraction convergents to sqrt(72).

Original entry on oeis.org

1, 2, 33, 68, 1121, 2310, 38081, 78472, 1293633, 2665738, 43945441, 90556620, 1492851361, 3076259342, 50713000833, 104502261008, 1722749176961, 3550000614930, 58522759015841, 120595518646612, 1988051057361633, 4096697633369878, 67535213191279681
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Magma
    I:=[1, 2, 33, 68]; [n le 4 select I[n] else 34*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 11 2013
  • Mathematica
    Denominator/@Convergents[Sqrt[72], 50] (* Vladimir Joseph Stephan Orlovsky, Jul 05 2011 *)
    CoefficientList[Series[(1 + 2 x - x^2)/(x^4 - 34 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 11 2013 *)
    a0[n_] := ((3+2*Sqrt[2])/(17+12*Sqrt[2])^n+(3-2*Sqrt[2])*(17+ 12*Sqrt[2])^n)/6 // Simplify
    a1[n_] := (-1/(17+12*Sqrt[2])^n+(17+12*Sqrt[2])^n)/(12*Sqrt[2]) // FullSimplify
    Flatten[MapIndexed[{a0[#],a1[#]}&,Range[20]]] (* Gerry Martens, Jul 10 2015 *)
  • PARI
    a(n)=my(v=contfrac(sqrt(72),n),s=v[n]);forstep(k=n-1,1,-1,s=v[k]+1/s);denominator(s) \\ Charles R Greathouse IV, Jul 05 2011
    

Formula

G.f.: -(x^2-2*x-1) / ((x^2-6*x+1)*(x^2+6*x+1)). - Colin Barker, Nov 13 2013
a(n) = 34*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 11 2013
From Gerry Martens, Jul 11 2015: (Start)
Interspersion of 2 sequences [a0(n),a1(n)] for n>0:
a0(n) = ((3+2*sqrt(2))/(17+12*sqrt(2))^n+(3-2*sqrt(2))*(17+12*sqrt(2))^n)/6.
a1(n) = (-1/(17+12*sqrt(2))^n+(17+12*sqrt(2))^n)/(12*sqrt(2)). (End)

A386461 Decimal expansion of the surface area of a biaugmented truncated cube with unit edges.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jul 23 2025

Keywords

Comments

The biaugmented truncated cube is Johnson solid J_67.

Examples

			36.241911729260269564523295159701074096328596018257...
		

Crossrefs

Cf. A010524 (volume - 9).

Programs

  • Mathematica
    First[RealDigits[18 + 8*Sqrt[2] + Sqrt[48], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["J67", "SurfaceArea"], 10, 100]]

Formula

Equals 2*(9 + 4*sqrt(2) + 2*sqrt(3)) = 2*(9 + A010487 + A010469) = 18 + A377342 + A010502.
Equals the largest root of x^4 - 72*x^3 + 1592*x^2 - 10656*x - 2672.

A178988 Decimal expansion of volume of golden tetrahedron.

Original entry on oeis.org

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

Views

Author

Jonathan Vos Post, Jan 03 2011

Keywords

Comments

Volume of tetrahedron with edges 1, phi, phi^2, phi^3, phi^4, phi^5 where phi is the golden ratio (1+sqrt(5))/2.
A152149 records more recent developments about side-golden and angle-golden triangles, both of which, like the golden rectangle, have generalizations that match continued fractions. There is a unique triangle which is both side-golden and angle-golden. Is there a comparable tetrahedron? - Clark Kimberling, Mar 31 2011

Examples

			75.7552212810...
		

References

  • Clark Kimberling, "A New Kind of Golden Triangle." In Applications of Fibonacci Numbers: Proceedings of the Fourth International Conference on Fibonacci Numbers and Their Applications,' Wake Forest University (Ed. G. E. Bergum, A. N. Philippou, and A. F. Horadam). Dordrecht, Netherlands: Kluwer, pp. 171-176, 1991.
  • Theoni Pappas, "The Pentagon, the Pentagram & the Golden Triangle." The Joy of Mathematics. San Carlos, CA: Wide World Publ./Tetra, pp. 188-189, 1989.

Crossrefs

Programs

  • Mathematica
    RealDigits[Sqrt[275465/96 + 369575*Sqrt[5]/288], 10, 120][[1]] (* Amiram Eldar, Jun 12 2023 *)
  • PARI
    sqrt(275465/96 + (369575*sqrt(5))/288) \\ Charles R Greathouse IV, May 27 2016

Formula

Equals sqrt(275465/96 + (369575*sqrt(5))/288).
The minimal polynomial is 20736*x^4 - 119000880*x^2 + 73225. - Joerg Arndt, Jul 25 2021

Extensions

a(101) corrected by Georg Fischer, Jul 25 2021

A381686 Decimal expansion of the isoperimetric quotient of a truncated cube.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 04 2025

Keywords

Comments

For the definition of isoperimetric quotient of a solid, references and links, see A381684.

Examples

			0.61302821107928032110240558144714079708976169223933...
		

Crossrefs

Cf. A377298 (surface area), A377299 (volume).

Programs

  • Mathematica
    First[RealDigits[49*Pi*(17 + 12*Sqrt[2])/(2*(6 + 6*Sqrt[2] + Sqrt[3])^3), 10, 100]]

Formula

Equals 36*Pi*A377299^2/(A377298^3).
Equals 49*Pi*(17 + 12*sqrt(2))/(2*(6 + 6*sqrt(2) + sqrt(3))^3) = 49*A000796*A156164/(2*(6 + A010524 + A002194)^3).
Previous Showing 11-18 of 18 results.