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 11-16 of 16 results.

A119886 a(n) = 20*a(n-2) - 64*a(n-4).

Original entry on oeis.org

1, 59, 2416, 6230, 47680, 120824, 798976, 2017760, 12928000, 32622464, 207425536, 523312640, 3321118720, 8378415104, 53147140096, 134076293120, 850391203840, 2145307295744, 13606407110656, 34325263155200, 217703105167360, 549205596176384, 3483252048265216
Offset: 0

Views

Author

Roger L. Bagula, Aug 09 2006

Keywords

Links

Crossrefs

Cf. A060595, A060638, A002409, A099193, A000937, A099195.

Programs

  • Mathematica
    M = {{0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0}, {1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0}, {0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0}, {1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0}, {0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0}, {0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0}, {0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0}, {1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1}, {1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1}, {0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0}, {0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0}, {0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0}, {0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1}, {0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0}, {0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1}, {0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0}} v[1] = Table[Fibonacci[n], {n, 1, 16}] v[n_] := v[n] = M.v[n - 1] a = Table[Floor[v[n][[1]]], {n, 1, 50}]
(* Second program: *)
A = SparseArray[{{1, 8} -> 1, Band[{1, 4}] -> 1, Band[{1, 2}, {3, 4}] -> 1, Band[{5, 6}, {7, 8}] -> 1}, {8, 8}]; M = ArrayFlatten[{{A+Transpose[A], IdentityMatrix[8]}, {IdentityMatrix[8], A+Transpose[A]}}]; v[1] = Array[ Fibonacci, 16]; v[n_] := v[n] = M.v[n-1]; A119886 = Array[v, 50][[All, 1]] (* Jean-François Alcover, Feb 05 2017 *)
LinearRecurrence[{0,20,0,-64},{1,59,2416,6230,47680},30] (* Harvey P. Dale, Sep 06 2024 *)
  • PARI
    Vec(-(576*x^4-5050*x^3-2396*x^2-59*x-1) / ((2*x-1)*(2*x+1)*(4*x-1)*(4*x+1)) + O(x^30)) \\ Colin Barker, Feb 05 2017

Formula

G.f.: -(576*x^4-5050*x^3-2396*x^2-59*x-1) / ((2*x-1)*(2*x+1)*(4*x-1)*(4*x+1)). - Colin Barker, Nov 17 2012
a(n) = 2^(n-4)*(-3266 + 585*(-2)^n + 258*(-1)^n + 2583*2^n) for n>0. - Colin Barker, Feb 05 2017

Extensions

New name from Joerg Arndt, Feb 05 2017

A060615 Number of conjugacy classes in the group GL_2(K) when K is a finite field with q = p^m for a prime p and m >= 1.

Original entry on oeis.org

3, 8, 15, 24, 48, 63, 80, 120, 168, 255, 288, 360, 528, 624, 728, 840, 960, 1023, 1368, 1680, 1848, 2208, 2400, 2808, 3480, 3720, 4095, 4488, 5040, 5328, 6240, 6560, 6888, 7920, 9408, 10200, 10608, 11448, 11880, 12768, 14640, 15624, 16128, 16383, 17160
Offset: 0

Views

Author

Ahmed Fares (ahmedfares(AT)my-deja.com), Apr 13 2001

Keywords

Comments

The number of conjugacy classes in the group GL_2(K) is q^2 - 1 so this sequence is a subsequence of A005563 restricted to q = prime power. The order of the group GL_2(K) is in A059238.

Crossrefs

A000961, A005563, A059238. A diagonal of A060638.

Programs

  • Maple
    with(numtheory): for n from 2 to 400 do if nops(ifactors(n)[2]) = 1 then printf(`%d,`, n^2-1) fi: od:

Formula

a(n) = A000961(n+2)^2 - 1. - Sean A. Irvine, Dec 04 2022

Extensions

More terms from James Sellers, Apr 14 2001

A060617 Number of flips between the d-dimensional tilings of the unary zonotope Z(D,d). Here d=7 and D varies.

Original entry on oeis.org

0, 1, 18, 9600
Offset: 7

Views

Author

Matthieu Latapy (latapy(AT)liafa.jussieu.fr), Apr 13 2001

Keywords

Examples

			For any Z(d,d), there is a unique tiling therefore the first term of the series is 0. Likewise, there are always two tilings of Z(d+1,d) with a flip between them, therefore the second term of the series is 1.

References

  • A. Bjorner, M. Las Vergnas, B. Sturmfels, N. White and G. M. Ziegler, Oriented Matroids, Encyclopedia of Mathematics 46, Second Edition, Cambridge University Press, 1999.
  • N. Destainville, R. Mosseri and F. Bailly, Fixed-boundary octagonal random tilings: a combinatorial approach, Journal of Statistical Physics, 102 (2001), no. 1-2, 147-190.
  • Victor Reiner, The generalized Baues problem, in New Perspectives in Algebraic Combinatorics (Berkeley, CA, 1996-1997), 293-336, Math. Sci. Res. Inst. Publ., 38, Cambridge Univ. Press, Cambridge, 1999.

Links

Crossrefs

Cf. A001286 (case where d=1). Cf. A060595 (number of 3-tilings) for terminology. A diagonal of A060638.

A060618 Number of flips between the d-dimensional tilings of the unary zonotope Z(D,d). Here d=8 and D varies.

Original entry on oeis.org

0, 1, 20, 22528
Offset: 8

Views

Author

Matthieu Latapy (latapy(AT)liafa.jussieu.fr), Apr 13 2001

Keywords

Examples

			For any Z(d,d), there is a unique tiling therefore the first term of the series is 0. Likewise, there are always two tilings of Z(d+1,d) with a flip between them, therefore the second term of the series is 1.

References

  • A. Bjorner, M. Las Vergnas, B. Sturmfels, N. White and G. M. Ziegler, Oriented Matroids, Encyclopedia of Mathematics 46, Second Edition, Cambridge University Press, 1999.
  • N. Destainville, R. Mosseri and F. Bailly, Fixed-boundary octagonal random tilings: a combinatorial approach, Journal of Statistical Physics, 102 (2001), no. 1-2, 147-190.
  • Victor Reiner, The generalized Baues problem, in New Perspectives in Algebraic Combinatorics (Berkeley, CA, 1996-1997), 293-336, Math. Sci. Res. Inst. Publ., 38, Cambridge Univ. Press, Cambridge, 1999.

Links

Crossrefs

Cf. A001286 (case where d=1). Cf. A060595 (number of 3-tilings) for terminology. A diagonal of A060638.

A060622 Number of flips between the d-dimensional tilings of the unary zonotope Z(D,d). Here the codimension D-d is equal to 4 and d varies.

Original entry on oeis.org

32, 240, 2144, 22624
Offset: 0

Views

Author

Matthieu Latapy (latapy(AT)liafa.jussieu.fr), Apr 13 2001

Keywords

Examples

			For any Z(d,d), there is a unique tiling therefore the first term of the series is 0. Likewise, there are always two tilings of Z(d+1,d) with a flip between them, therefore the second term of the series is 1.

References

  • A. Bjorner, M. Las Vergnas, B. Sturmfels, N. White and G. M. Ziegler, Oriented Matroids, Encyclopedia of Mathematics 46, Second Edition, Cambridge University Press, 1999.
  • N. Destainville, R. Mosseri and F. Bailly, Fixed-boundary octagonal random tilings: a combinatorial approach, Journal of Statistical Physics, 102 (2001), no. 1-2, 147-190.
  • Victor Reiner, The generalized Baues problem, in New Perspectives in Algebraic Combinatorics (Berkeley, CA, 1996-1997), 293-336, Math. Sci. Res. Inst. Publ., 38, Cambridge Univ. Press, Cambridge, 1999.

Links

Crossrefs

Cf. A060595 (number of 3-tilings) for terminology. A diagonal of A060638.

A060623 Number of flips between the d-dimensional tilings of the unary zonotope Z(D,d). Here the codimension D-d is equal to 5 and d varies.

Original entry on oeis.org

80, 1800, 80360
Offset: 0

Views

Author

Matthieu Latapy (latapy(AT)liafa.jussieu.fr), Apr 13 2001

Keywords

References

  • A. Bjorner, M. Las Vergnas, B. Sturmfels, N. White and G. M. Ziegler, Oriented Matroids, Encyclopedia of Mathematics 46, Second Edition, Cambridge University Press, 1999.
  • N. Destainville, R. Mosseri and F. Bailly, Fixed-boundary octagonal random tilings: a combinatorial approach, Journal of Statistical Physics, 102 (2001), no. 1-2, 147-190.
  • Victor Reiner, The generalized Baues problem, in New Perspectives in Algebraic Combinatorics (Berkeley, CA, 1996-1997), 293-336, Math. Sci. Res. Inst. Publ., 38, Cambridge Univ. Press, Cambridge, 1999.

Links

Crossrefs

Cf. A060595 (number of 3-tilings) for terminology. A diagonal of A060638.
Previous Showing 11-16 of 16 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.