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.

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A208922 Triangle of coefficients of polynomials v(n,x) jointly generated with A208921; see the Formula section.

Original entry on oeis.org

1, 3, 1, 5, 4, 2, 7, 13, 12, 2, 9, 32, 40, 16, 4, 11, 65, 108, 80, 36, 4, 13, 116, 258, 288, 180, 48, 8, 15, 189, 560, 842, 700, 324, 96, 8, 17, 288, 1120, 2144, 2312, 1536, 640, 128, 16, 19, 417, 2088, 4944, 6728, 5832, 3232, 1088, 240, 16, 21, 580, 3666
Offset: 1

Views

Author

Clark Kimberling, Mar 04 2012

Keywords

Comments

Alternating row sums: 1,2,3,4,5,6,7,8,9,10,...
For a discussion and guide to related arrays, see A208510.

Examples

			First five rows:
1
3...1
5...4....2
7...13...12...2
9...32...40...16...4
First five polynomials v(n,x):
1
3 + x
5 + 4x + 2x^2
7 + 13x + 12x^2 + 2x^3
9 + 32x + 40x^2 + 16x^3 + 4x^4
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + 2x*v[n - 1, x];
    v[n_, x_] := (x + 1)*u[n - 1, x] + v[n - 1, x] + 1;
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A208921 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208922 *)

Formula

u(n,x)=u(n-1,x)+2x*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.

A208923 Triangle of coefficients of polynomials u(n,x) jointly generated with A208908; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 6, 4, 1, 10, 14, 8, 1, 14, 32, 38, 16, 1, 18, 58, 104, 90, 32, 1, 22, 92, 222, 296, 214, 64, 1, 26, 134, 408, 738, 808, 490, 128, 1, 30, 184, 678, 1552, 2286, 2104, 1110, 256, 1, 34, 242, 1048, 2906, 5392, 6674, 5320, 2474, 512, 1, 38, 308
Offset: 1

Views

Author

Clark Kimberling, Mar 04 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.

Examples

			First five rows:
1
1...2
1...6....4
1...10...14...8
1...14...32...38...16
First five polynomials u(n,x):
1
1 + 2x
1 + 6x + 4x^2
1 + 10x + 14x^2 + 8x^3
1 + 14x + 32x^2 + 38x^3 + 16x^4
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + 2 x*v[n - 1, x];
    v[n_, x_] := (x + 1)*u[n - 1, x] + x*v[n - 1, x] + 1;
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A208923 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208908 *)

Formula

u(n,x)=u(n-1,x)+2x*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+x*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.

A208931 Triangle of coefficients of polynomials u(n,x) jointly generated with A208932; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 8, 4, 1, 18, 20, 8, 1, 32, 64, 56, 16, 1, 50, 160, 224, 136, 32, 1, 72, 340, 680, 664, 328, 64, 1, 98, 644, 1736, 2416, 1872, 760, 128, 1, 128, 1120, 3920, 7264, 7856, 4984, 1736, 256, 1, 162, 1824, 8064, 19056, 26992, 23768, 12832, 3896
Offset: 1

Views

Author

Clark Kimberling, Mar 04 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.

Examples

			First five rows:
1
1...2
1...8....4
1...18...20...8
1...32...64...56...16
First five polynomials u(n,x):
1
1 + 2x
1 + 8x + 4x^2
1 + 18x + 20x^2 + 8x^3
1 + 32x + 64x^2 + 56x^3 + 16x^4
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + 2 x*v[n - 1, x];
    v[n_, x_] := (x + 1)*u[n - 1, x] + (x + 1)*v[n - 1, x] + 1;
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A208931 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208932 *)

Formula

u(n,x)=u(n-1,x)+2x*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+(x+1)*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.

A208932 Triangle of coefficients of polynomials v(n,x) jointly generated with A208932; see the Formula section.

Original entry on oeis.org

1, 3, 2, 5, 8, 4, 7, 22, 24, 8, 9, 48, 84, 60, 16, 11, 90, 228, 264, 148, 32, 13, 152, 528, 876, 772, 348, 64, 15, 238, 1092, 2424, 2992, 2112, 804, 128, 17, 352, 2072, 5896, 9568, 9392, 5548, 1820, 256, 19, 498, 3672, 13008, 26648, 34080, 27780
Offset: 1

Views

Author

Clark Kimberling, Mar 04 2012

Keywords

Comments

Alternating row sums: 1,1,1,1,1,1,1,1,1,1,1,1,1,...
For a discussion and guide to related arrays, see A208510.

Examples

			First five rows:
1
3...2
5...8....4
7...22...24...8
9...48...84...60...16
First five polynomials v(n,x):
1
3 + 2x
5 + 8x + 4x^2
7 + 22x + 24x^2 + 8x^3
9 + 48x + 84x^2 + 60x^3 + 16x^4
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + 2 x*v[n - 1, x];
    v[n_, x_] := (x + 1)*u[n - 1, x] + (x + 1)*v[n - 1, x] + 1;
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A208931 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208932 *)

Formula

u(n,x)=u(n-1,x)+2x*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+(x+1)*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.

A209125 Triangle of coefficients of polynomials u(n,x) jointly generated with A164975; see the Formula section.

Original entry on oeis.org

1, 2, 1, 3, 4, 2, 5, 9, 9, 4, 8, 20, 25, 20, 8, 13, 40, 65, 65, 44, 16, 21, 78, 150, 190, 162, 96, 32, 34, 147, 331, 490, 521, 392, 208, 64, 55, 272, 697, 1192, 1473, 1368, 928, 448, 128, 89, 495, 1425, 2745, 3888, 4185, 3480, 2160, 960, 256, 144, 890
Offset: 1

Views

Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

Alternating row sums: 1,1,1,1,1,1,1,1,1,1,1,1,1,...
For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (1, 1, -1, 0, 0, 0, 0, 0, 0, 0, ....) DELTA (0, 1, 1, 0, 0, 0, 0, 0, 0, 0, ....) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 21 2012

Examples

			First five rows:
  1;
  2,  1;
  3,  4,  2;
  5,  9,  9,  4;
  8, 20, 25, 20,  8;
First three polynomials u(n,x):
  1
  2 + x
  3 + 4x + 2x^2
From _Philippe Deléham_, Mar 21 2012: (Start)
(1, 1, -1, 0, 0, ...) DELTA (0, 1, 1, 0, 0, ...) begins:
  1;
  1,  0;
  2,  1,  0;
  3,  4,  2,  0;
  5,  9,  9,  4, 0;
  8, 20, 25, 20, 8, 0; (End)
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := u[n - 1, x] + 2 x*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A209125 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A164975 *)

Formula

u(n,x) = u(n-1,x) + (x+1)*v(n-1,x),
v(n,x) = u(n-1,x) + 2x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 21 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-2*y*x)/(1-x-2*y*x-x^2+y*x^2).
T(n,k) = T(n-1,k) + 2*T(n-1,k-1) + T(n-2,k) - T(n-2,k-1), T(0,0) = T(1,0) = T(2,1) = 1, T(1,1) = T(2,2) = 0, T(2,0) = 2, T(n,k) = 0 f k < 0 or if k > n. (End)

A209126 Triangle of coefficients of polynomials u(n,x) jointly generated with A209127; see the Formula section.

Original entry on oeis.org

1, 2, 1, 2, 3, 2, 2, 5, 7, 3, 2, 7, 14, 13, 5, 2, 9, 23, 32, 25, 8, 2, 11, 34, 62, 71, 46, 13, 2, 13, 47, 105, 156, 149, 84, 21, 2, 15, 62, 163, 295, 367, 304, 151, 34, 2, 17, 79, 238, 505, 767, 827, 604, 269, 55, 2, 19, 98, 332, 805, 1435, 1889, 1798, 1177, 475
Offset: 1

Views

Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

u(n,n) = A000045(n), Fibonacci numbers.
Alternating row sums: 1,1,1,1,1,1,1,1,1,1,1,1,1,...
For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (1, 1, -2, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 1, 1, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 21 2012

Examples

			First five rows:
  1;
  2,  1;
  2,  3,  2;
  2,  5,  7,  3;
  2,  7, 14, 13,  5;
First three polynomials u(n,x):
  1
  2 + x
  2 + 3x + 2x^2
From _Philippe Deléham_, Mar 21 2012: (Start)
(1, 1, -2, 1, 0, 0, ...) DELTA (0, 1, 1, -1, 0, 0, ...) begins:
  1;
  1,  0;
  2,  1,  0;
  2,  3,  2,  0;
  2,  5,  7,  3,  0;
  2,  7, 14, 13,  5,  0; (End)
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := x*u[n - 1, x] + x*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A209126 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A209127 *)

Formula

u(n,x) = u(n-1,x) + (x+1)*v(n-1,x),
v(n,x) = x*u(n-1,x) + x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 21 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-y*x+x^2-y^2*x^2)/(1-x-y*x-y^2*x^2).
T(n,k) = T(n-1,k) + T(n-1,k-1) + T(n-2,k-2), T(0,0) = T(1,0) = T(2,1) = 1, T(1,1) = T(2,2) = 0, T(2,0) = 2 and T(n,k) = 0 if k < 0 or if k > n. (End)

A209127 Triangle of coefficients of polynomials v(n,x) jointly generated with A209126; see the Formula section.

Original entry on oeis.org

1, 0, 2, 0, 2, 3, 0, 2, 5, 5, 0, 2, 7, 12, 8, 0, 2, 9, 21, 25, 13, 0, 2, 11, 32, 53, 50, 21, 0, 2, 13, 45, 94, 124, 96, 34, 0, 2, 15, 60, 150, 250, 273, 180, 55, 0, 2, 17, 77, 223, 445, 617, 577, 331, 89, 0, 2, 19, 96, 315, 728, 1212, 1444, 1181, 600, 144, 0, 2, 21
Offset: 1

Views

Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

u(n,n)=(1,2,3,5,8,13,21,...)=A000045(n+1), Fibonacci numbers.
Alternating row sums: (1,-2,1,-2,1,-2,1,-2,...
For a discussion and guide to related arrays, see A208510.
As triangle T(n,k) with 0<=k<=n, it is (0, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (2, -1/2, -1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 21 2012

Examples

			First five rows:
1
0...2
0...2...3
0...2...5...5
0...2...7...12...8
First three polynomials v(n,x): 1, 2x, 2x + 3x^2.
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := x*u[n - 1, x] + x*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A209126 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A209127 *)

Formula

u(n,x)=u(n-1,x)+(x+1)*v(n-1,x),
v(n,x)=x*u(n-1,x)+x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
T(n,k) = T(n-1,k) + T(n-1,k-1) + T(n-2,k-2), T(1,0) = 1, T(2,0) = 0, T(2,1) = 2, T(n,k) = 0 if k<0 or if k>=n. - Philippe Deléham, Mar 21 2012
G.f.: (-1-x*y+x)*x*y/(-1+x*y+x+x^2*y^2). - R. J. Mathar, Aug 12 2015

A209128 Triangle of coefficients of polynomials u(n,x) jointly generated with A209129; see the Formula section.

Original entry on oeis.org

1, 2, 1, 2, 4, 3, 2, 6, 12, 7, 2, 8, 22, 32, 17, 2, 10, 34, 70, 86, 41, 2, 12, 48, 124, 216, 228, 99, 2, 14, 64, 196, 428, 644, 600, 239, 2, 16, 82, 288, 744, 1408, 1876, 1568, 577, 2, 18, 102, 402, 1188, 2664, 4476, 5364, 4074, 1393, 2, 20, 124, 540, 1786
Offset: 1

Views

Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (1, 1, -2, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 1, 2, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 21 2012
Row sums are powers of 3 (A000244). - Philippe Deléham, Mar 21 2012

Examples

			First five rows:
  1;
  2,  1;
  2,  4,  3;
  2,  6, 12,  7;
  2,  8, 22, 32, 17;
First three polynomials u(n,x):
  1
  2 + x
  2 + 4x + 3x^2
From _Philippe Deléham_, Mar 21 2012: (Start)
(1, 1, -2, 1, 0, 0, ...) DELTA (0, 1, 2, -1, 0, 0, ...) begins:
  1;
  1,  0;
  2,  1,  0;
  2,  4,  3,  0;
  2,  6, 12,  7,  0;
  2,  8, 22, 32, 17,  0; (End)
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := x*u[n - 1, x] + 2 x*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A209128 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A209129 *)

Formula

u(n,x) = u(n-1,x) + (x+1)*v(n-1,x),
v(n,x) = x*u(n-1,x) + 2x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 21 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-2*y*x+x^2-y^2*x^2)/(1-x-2*y*x+y*x^2-y^2*x^2).
T(n,k) = T(n-1,k-1) + 2*T(n-1,k-1) - T(n-2,k-1) + T(n-2,k-2), T(0,0) = T(1,0) = T(2,1) = 1, T(1,1) = T(2,2) = 0, T(2,0) = 2 and T(n,k) = 0 if k < 0 or if k > n. (End)

A209129 Triangle of coefficients of polynomials v(n,x) jointly generated with A209128; see the Formula section.

Original entry on oeis.org

1, 0, 3, 0, 2, 7, 0, 2, 8, 17, 0, 2, 10, 28, 41, 0, 2, 12, 42, 88, 99, 0, 2, 14, 58, 154, 262, 239, 0, 2, 16, 76, 240, 524, 752, 577, 0, 2, 18, 96, 348, 908, 1692, 2104, 1393, 0, 2, 20, 118, 480, 1440, 3224, 5260, 5776, 3363, 0, 2, 22, 142, 638, 2148, 5544
Offset: 1

Views

Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
As triangle T(n,k) with 0<=k<=n, it is (0, 2/3, 1/3, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (3, -2/3, -1/3, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 21 2012

Examples

			First five rows:
1
0...3
0...2....7
0...2....8...17
0...2...10...28...41
First three polynomials v(n,x): 1, 3x, 2x + 7x^2.
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := x*u[n - 1, x] + 2 x*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A209128 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A209129 *)

Formula

u(n,x)=u(n-1,x)+(x+1)*v(n-1,x),
v(n,x)=x*u(n-1,x)+2x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
T(n,k) = T(n-1,k) + 2*T(n-1,k-1) - T(n-2,k-1) + T(n-2,k-2), T(1,0) = 1, T(2,0) = 0, T(2,1) = 3 and T(n,k) = 0 if k<0 or if k>=n. - Philippe Deléham, Mar 21 2012
G.f.: (-1+x-x*y)*x*y/(-1+x+2*x*y-x^2*y+x^2*y^2). - R. J. Mathar, Aug 12 2015

A209130 Triangle of coefficients of polynomials v(n,x) jointly generated with A102756; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 5, 3, 1, 9, 12, 5, 1, 14, 31, 27, 8, 1, 20, 65, 89, 55, 13, 1, 27, 120, 230, 222, 108, 21, 1, 35, 203, 511, 684, 514, 205, 34, 1, 44, 322, 1022, 1777, 1834, 1125, 381, 55, 1, 54, 486, 1890, 4095, 5442, 4563, 2367, 696, 89, 1, 65, 705, 3288, 8625
Offset: 1

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Author

Clark Kimberling, Mar 05 2012

Keywords

Comments

Top edge: (1,2,3,5,8,...) = A000045(n+1), Fibonacci numbers.
Alternating row sums: 1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,...
For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle T(n,k) given by (1, 0, 1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 2, -1/2, -1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 08 2012

Examples

			First five rows:
  1;
  1,  2;
  1,  5,  3;
  1,  9, 12,  5;
  1, 14, 31, 27,  8;
First three polynomials v(n,x):
  1
  1 + 2x
  1 + 5x + 3x^2.
From _Philippe Deléham_, Mar 08 2012: (Start)
(1, 0, 1/2, 1/2, 0, 0, 0, ...) DELTA (0, 2, -1/2, -1/2, 0, 0, 0, 0...) begins:
  1;
  1,  0;
  1,  2,  0;
  1,  5,  3,  0;
  1,  9, 12,  5,  0;
  1, 14, 31, 27,  8,  0;
  1, 20, 65, 89, 55, 13, 0; ...
with row sums 1, 1, 3, 9, 27, 81, 243, 729, ... (powers of 3). (End)
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
    v[n_, x_] := x*u[n - 1, x] + (x + 1)*v[n - 1, x];
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]    (* A102756 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A209130 *)

Formula

u(n,x) = u(n-1,x) + (x+1)*v(n-1,x),
v(n,x) = x*u(n-1,x) + (x+1)*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 08 2012: (Start)
As DELTA-triangle T(n,k) with 0 <= k <= n:
T(n,k) = 2*T(n-1,k) + T(n-1,k-1) - T(n-2,k) + T(n-2,k-2), T(0,0) = 1, T(1,0) = 1, T(1,1) = 0 and T(n,k) = 0 if k < 0 or if k > n.
G.f.: (1-x-y*x+y*x^2-y^2*x^2)/(1-(2+y)*x-(y^2-1)*x^2).
Sum_{k=0..n, n>=1} T(n,k)*x^k = A153881(n), A000012(n), A000244(n-1), A126473(n-1) for x = -1, 0, 1, 2 respectively. (End)
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