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 21-30 of 30 results.

A015323 Gaussian binomial coefficient [ n,6 ] for q = -2.

Original entry on oeis.org

1, 43, 3655, 208335, 14208447, 882215391, 57344000415, 3642010817055, 233988483199263, 14946527496991519, 957498220445101855, 61250446192484546335, 3920970870875818419999, 250911985465716094666527
Offset: 6

Views

Author

Olivier Gérard, Dec 11 1999

Keywords

References

  • J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
  • I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
  • M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Crossrefs

Diagonal k=6 of the triangular array A015109. See there for further references and programs. - M. F. Hasler, Nov 04 2012

Programs

  • Mathematica
    Table[QBinomial[n, 6, -2], {n, 6, 20}] (* Vincenzo Librandi, Oct 29 2012 *)
  • Sage
    [gaussian_binomial(n,6,-2) for n in range(6,20)] # Zerinvary Lajos, May 27 2009

Formula

A015323(n) = T[n,6] where T is the triangular array A015109. - M. F. Hasler, Nov 04 2012
G.f.: x^6 / ( (x-1)*(8*x+1)*(64*x-1)*(2*x+1)*(32*x+1)*(4*x-1)*(16*x-1) ). - R. J. Mathar, Aug 04 2016

A015338 Gaussian binomial coefficient [ n,7 ] for q = -2.

Original entry on oeis.org

1, -85, 14535, -1652145, 225683007, -28005209505, 3642010817055, -462535373765985, 59438516325245343, -7593183562134412385, 972884994173649887135, -124468028808034701006945
Offset: 7

Views

Author

Olivier Gérard, Dec 11 1999

Keywords

References

  • J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
  • I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
  • M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Crossrefs

Diagonal k=7 of the triangular array A015109. See there for further references and programs. - M. F. Hasler, Nov 04 2012

Programs

  • Magma
    /* By definition: */ r:=7; q:=-2; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Bruno Berselli, Oct 30 2012
  • Mathematica
    Table[QBinomial[n, 7, -2], {n, 7, 20}] (* Vincenzo Librandi, Oct 29 2012 *)
  • Sage
    [gaussian_binomial(n,7,-2) for n in range(7,19)] # Zerinvary Lajos, May 27 2009
    

A015405 Gaussian binomial coefficient [ n,11 ] for q=-2.

Original entry on oeis.org

1, -1365, 3727815, -6785865905, 14824402656063, -29439916001972385, 61250446192484546335, -124468028808034701006945, 255910660218571393553843871, -523082886040328458081329117025
Offset: 11

Views

Author

Keywords

References

  • J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
  • I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
  • M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Crossrefs

Diagonal k=11 of the triangular array A015109. See there for further references and programs. - M. F. Hasler, Nov 04 2012

Programs

  • Magma
    r:=11; q:=-2; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..25]]; // Vincenzo Librandi, Nov 05 2012
  • Mathematica
    Table[QBinomial[n, 11, -2], {n, 11, 20}] (* Vincenzo Librandi, Nov 05 2012 *)
  • Sage
    [gaussian_binomial(n,11,-2) for n in range(11,21)] # Zerinvary Lajos, May 28 2009
    

Formula

a(n) = Product_{i=1..11} ((-2)^(n-i+1)-1)/((-2)^i-1). - Vincenzo Librandi, Nov 05 2012

A015423 Gaussian binomial coefficient [ n,12 ] for q=-2.

Original entry on oeis.org

1, 2731, 14913991, 54301841231, 237244744338239, 942314556807454559, 3920970870875818419999, 15935828658299317547308959, 65529064844612576067331339935, 267883966717492783113707839256735
Offset: 12

Views

Author

Keywords

References

  • J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
  • I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
  • M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Crossrefs

Diagonal k=12 of the triangular array A015109. See there for further references and programs. - M. F. Hasler, Nov 04 2012

Programs

  • Magma
    r:=12; q:=-2; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..25]]; // Vincenzo Librandi, Nov 06 2012
  • Mathematica
    Table[QBinomial[n, 12, -2], {n, 12, 20}] (* Vincenzo Librandi, Nov 06 2012 *)
  • Sage
    [gaussian_binomial(n,12,-2) for n in range(12,22)] # Zerinvary Lajos, May 28 2009
    

Formula

a(n) = Product_{i=1..12} ((-2)^(n-i+1)-1)/((-2)^i-1) (by definition). - Vincenzo Librandi, Nov 06 2012

A172349 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=4.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 5, 5, 1, 1, 9, 45, 9, 1, 1, 29, 261, 261, 29, 1, 1, 65, 1885, 3393, 1885, 65, 1, 1, 181, 11765, 68237, 68237, 11765, 181, 1, 1, 441, 79821, 1037673, 3343613, 1037673, 79821, 441, 1, 1, 1165, 513765, 18598293, 134321005, 134321005
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Feb 01 2010

Keywords

Comments

Start from the generalized Fibonacci sequence A006131 and its partial products c(n) = 1, 1, 1, 5, 45, 1305, 84825, 15353325, 6770816325, 7888001018625... Then t(n,k) = c(n)/(c(k)*c(n-k)).
Row sums are 1, 2, 3, 12, 65, 582, 7295, 160368, 5579485, 306868458, 26280601275,...

Examples

			1;
1, 1;
1, 1, 1;
1, 5, 5, 1;
1, 9, 45, 9, 1;
1, 29, 261, 261, 29, 1;
1, 65, 1885, 3393, 1885, 65, 1;
1, 181, 11765, 68237, 68237, 11765, 181, 1;
1, 441, 79821, 1037673, 3343613, 1037673, 79821, 441, 1;
1, 1165, 513765, 18598293, 134321005, 134321005, 18598293, 513765, 1165, 1;
1, 2929, 3412285, 300963537, 6052711133, 13566421505, 6052711133, 300963537, 3412285, 2929, 1;
		

Crossrefs

Cf. A010048 (m=1), A015109 (m=2), A172347 (m=3), A172350 (m=5).

Programs

  • Mathematica
    Clear[f, c, a, t];
    f[0, a_] := 0; f[1, a_] := 1;
    f[n_, a_] := f[n, a] = f[n - 1, a] + a*f[n - 2, a];
    c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];
    t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);
    Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];
    Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]

A172350 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=5.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 6, 6, 1, 1, 11, 66, 11, 1, 1, 41, 451, 451, 41, 1, 1, 96, 3936, 7216, 3936, 96, 1, 1, 301, 28896, 197456, 197456, 28896, 301, 1, 1, 781, 235081, 3761296, 14019376, 3761296, 235081, 781, 1, 1, 2286, 1785366, 89565861, 781665696
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Feb 01 2010

Keywords

Comments

Start from the generalized Fibonacci sequence A015440 and its partial products c(n) = 1, 1, 1, 6, 66, 2706, 259776, 78192576, 61068401856, 139602366642816... Then t(n,k) = c(n)/(c(k)*c(n-k)).
Row sums are 1, 2, 3, 14, 90, 986, 15282, 453308, 22013694, 1746038420, 222562828116,...

Examples

			1;
1, 1;
1, 1, 1;
1, 6, 6, 1;
1, 11, 66, 11, 1;
1, 41, 451, 451, 41, 1;
1, 96, 3936, 7216, 3936, 96, 1;
1, 301, 28896, 197456, 197456, 28896, 301, 1;
1, 781, 235081, 3761296, 14019376, 3761296, 235081, 781, 1;
1, 2286, 1785366, 89565861, 781665696, 781665696, 89565861, 1785366, 2286, 1;
1, 6191, 14152626, 1842200151, 50409295041, 118031520096, 50409295041, 1842200151, 14152626, 6191, 1;
		

Crossrefs

Cf. A010048 (m=1), A015109 (m=2), A172349 (m=4), A172351 (m=6).

Programs

  • Mathematica
    Clear[f, c, a, t];
    f[0, a_] := 0; f[1, a_] := 1;
    f[n_, a_] := f[n, a] = f[n - 1, a] + a*f[n - 2, a];
    c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];
    t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);
    Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];
    Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]

A172351 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=6.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 7, 7, 1, 1, 13, 91, 13, 1, 1, 55, 715, 715, 55, 1, 1, 133, 7315, 13585, 7315, 133, 1, 1, 463, 61579, 483835, 483835, 61579, 463, 1, 1, 1261, 583843, 11093017, 46931995, 11093017, 583843, 1261, 1, 1, 4039, 5093179, 336877411
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Feb 01 2010

Keywords

Comments

Start from the generalized Fibonacci sequence A015441 and its partial products c(n) = 1, 1, 1, 7, 91, 5005, 665665, 308202895, 388643850595, 1569732512553205... Then t(n,k) = c(n)/(c(k)*c(n-k)).
Row sums are 1, 2, 3, 16, 119, 1542, 28483, 1091756, 70288239, 7576979362, 1345651717403,..

Examples

			1;
1, 1;
1, 1, 1;
1, 7, 7, 1;
1, 13, 91, 13, 1;
1, 55, 715, 715, 55, 1;
1, 133, 7315, 13585, 7315, 133, 1;
1, 463, 61579, 483835, 483835, 61579, 463, 1;
1, 1261, 583843, 11093017, 46931995, 11093017, 583843, 1261, 1;
1, 4039, 5093179, 336877411, 3446515051, 3446515051, 336877411, 5093179, 4039, 1;
		

Crossrefs

Cf. A010048 (m=1), A015109 (m=2), A172350 (m=5), A172352 (m=7).

Programs

  • Mathematica
    Clear[f, c, a, t];
    f[0, a_] := 0; f[1, a_] := 1;
    f[n_, a_] := f[n, a] = f[n - 1, a] + a*f[n - 2, a];
    c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];
    t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);
    Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];
    Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]

A216206 a(n) = Product_{i=1..n} ((-2)^i-1).

Original entry on oeis.org

1, -3, -9, 81, 1215, -40095, -2525985, 325852065, 83092276575, -42626337882975, -43606743654283425, 89350217747626737825, 365889141676531491393375, -2997729737755822508985921375, -49111806293653640164716349886625, 1609344780436736134557590069434814625
Offset: 0

Views

Author

R. J. Mathar, Mar 12 2013

Keywords

Comments

Signed partial products of A062510. This implies that all terms from a(1) on are multiples of 3.

Crossrefs

Programs

  • Maple
    A216206 := proc(n)
            mul( (-2)^i-1, i=1..n) ;
    end proc:
  • Mathematica
    Table[(-1)^n QPochhammer[-2, -2, n], {n, 0, 15}] (* Bruno Berselli, Mar 13 2013 *)
    Table[Product[(-2)^k-1,{k,n}],{n,0,20}] (* Harvey P. Dale, Oct 21 2024 *)

Formula

A015109(n,k) = a(n)/(a(k)*a(n-k)).
a(n) = (-3)^n*A015013(n) for n>0, a(0)=1. - Bruno Berselli and Alonso del Arte, Mar 13 2013
a(n) ~ (-1)^(floor(n/2)+1) * c * 2^(n*(n+1)/2), where c = Product_{k>=1} (1 - 1/(-2)^k) = 1.21072413030105918013... (A330862). - Amiram Eldar, Aug 10 2025

A172347 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=3.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 7, 28, 7, 1, 1, 19, 133, 133, 19, 1, 1, 40, 760, 1330, 760, 40, 1, 1, 97, 3880, 18430, 18430, 3880, 97, 1, 1, 217, 21049, 210490, 571330, 210490, 21049, 217, 1, 1, 508, 110236, 2673223, 15275560, 15275560, 2673223, 110236, 508
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Feb 01 2010

Keywords

Comments

Start from the generalized Fibonacci sequence A006130 and its partial products c(n) = 1, 1, 1, 4, 28, 532, 21280, 2064160, 447922720, 227544741760... Then t(n,k) = c(n)/(c(k)*c(n-k)).
Row sums are 1, 2, 3, 10, 44, 306, 2932, 44816, 1034844, 36119056, 1882089488,...

Examples

			1;
1, 1;
1, 1, 1;
1, 4, 4, 1;
1, 7, 28, 7, 1;
1, 19, 133, 133, 19, 1;
1, 40, 760, 1330, 760, 40, 1;
1, 97, 3880, 18430, 18430, 3880, 97, 1;
1, 217, 21049, 210490, 571330, 210490, 21049, 217, 1;
1, 508, 110236, 2673223, 15275560, 15275560, 2673223, 110236, 508, 1;
1, 1159, 588772, 31940881, 442609351, 931809160, 442609351, 31940881, 588772, 1159, 1;
		

Crossrefs

Cf. A010048 (m=1), A015109 (m=2), A172349 (m=4).

Programs

  • Mathematica
    Clear[f, c, a, t];
    f[0, a_] := 0; f[1, a_] := 1;
    f[n_, a_] := f[n, a] = f[n - 1, a] + a*f[n - 2, a];
    c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];
    t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);
    Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];
    Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]

A172352 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=7.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 8, 8, 1, 1, 15, 120, 15, 1, 1, 71, 1065, 1065, 71, 1, 1, 176, 12496, 23430, 12496, 176, 1, 1, 673, 118448, 1051226, 1051226, 118448, 673, 1, 1, 1905, 1282065, 28205430, 133505702, 28205430, 1282065, 1905, 1, 1, 6616, 12603480
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Feb 01 2010

Keywords

Comments

Start from the generalized Fibonacci sequence A015442 and its partial products c(n) = 1, 1, 1, 8, 120, 8520, 1499520, 1009176960, 1922482108800... Then t(n,k) = c(n)/(c(k)*c(n-k)).
Row sums are 1, 2, 3, 18, 152, 2274, 48776, 2340696, 192484504, 27026705688, 6379354108992,...

Examples

			1;
1, 1;
1, 1, 1;
1, 8, 8, 1;
1, 15, 120, 15, 1;
1, 71, 1065, 1065, 71, 1;
1, 176, 12496, 23430, 12496, 176, 1;
1, 673, 118448, 1051226, 1051226, 118448, 673, 1;
1, 1905, 1282065, 28205430, 133505702, 28205430, 1282065, 1905, 1;
1, 6616, 12603480, 1060267755, 12440474992, 12440474992, 1060267755, 12603480, 6616, 1;
		

Crossrefs

CF. A010048 (m=1), A015109 (m=2), A172351 (m=6).

Programs

  • Mathematica
    Clear[f, c, a, t];
    f[0, a_] := 0; f[1, a_] := 1;
    f[n_, a_] := f[n, a] = f[n - 1, a] + a*f[n - 2, a];
    c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];
    t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);
    Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];
    Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]
Previous Showing 21-30 of 30 results.