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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A208660 Triangle of coefficients of polynomials u(n,x) jointly generated with A208904; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 8, 2, 1, 18, 14, 2, 1, 32, 52, 20, 2, 1, 50, 140, 104, 26, 2, 1, 72, 310, 380, 174, 32, 2, 1, 98, 602, 1106, 806, 262, 38, 2, 1, 128, 1064, 2744, 2924, 1472, 368, 44, 2, 1, 162, 1752, 6048, 8892, 6412, 2432, 492, 50, 2, 1, 200, 2730, 12168, 23652
Offset: 1

Views

Author

Clark Kimberling, Mar 03 2012

Keywords

Comments

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

Examples

			First five rows:
1
1...2
1...8....2
1...18...14...2
1...32...52...20...2
First five polynomials u(n,x):
1
1 + 2x
1 + 8x + 2x^2
1 + 18x + 14x^2 + 2x^3
1 + 32x + 52x^2 + 20x^3 + 2x^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_] := 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[%]    (* A208660 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208904 *)

Formula

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

A208749 Triangle of coefficients of polynomials u(n,x) jointly generated with A208750; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 6, 2, 1, 12, 10, 4, 1, 20, 32, 24, 4, 1, 30, 80, 88, 36, 8, 1, 42, 170, 256, 180, 72, 8, 1, 56, 322, 644, 660, 384, 104, 16, 1, 72, 560, 1456, 1992, 1568, 704, 192, 16, 1, 90, 912, 3024, 5256, 5360, 3392, 1344, 272, 32, 1, 110, 1410, 5856, 12552
Offset: 1

Views

Author

Clark Kimberling, Mar 02 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle T(n,k) given by (1, 0, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 2, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 14 2012

Examples

			First five rows:
  1;
  1,  2;
  1,  6,  2;
  1, 12, 10,  4;
  1, 20, 32, 24,  4;
First five polynomials u(n,x):
  1
  1 +  2x
  1 +  6x +  2x^2
  1 + 12x + 10x^2 +  4x^3
  1 + 20x + 32x^2 + 24x^3 + 4x^4
From _Philippe Deléham_, Mar 14 2012: (Start)
(1, 0, 1, 0, 0, 0, ...) DELTA (0, 2, -1, -1, 0, 0, ...) begins:
  1;
  1,  0;
  1,  2,  0;
  1,  6,  2,  0;
  1, 12, 10,  4,  0;
  1, 20, 32, 24,  4,  0;
  1, 30, 80, 88, 36,  8,  0; (End)
		

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] + 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[%]    (* A208749 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208750 *)

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),
where u(1,x)=1, v(1,x)=1.
As DELTA-triangle: g.f.: (1-x-2*y^2*x^2)/(1-2*x+x^2-2*y*x^2-2*y^2*x^2). - Philippe Deléham, Mar 14 2012
Recurrence: T(n,k) = 2*T(n-1,k) - T(n-2,k) + 2*T(n-2,k-1) + 2*T(n-2,k-2), T(0,0) = T(1,0) = 1, T(2,0) = 1, T(2,1) = 2, T(n,k) = 0 if k < 0 or if k > =n. - Philippe Deléham, Mar 14 2012

A208750 Triangle of coefficients of polynomials v(n,x) jointly generated with A208749; see the Formula section.

Original entry on oeis.org

1, 2, 1, 3, 4, 2, 4, 11, 10, 2, 5, 24, 32, 16, 4, 6, 45, 84, 72, 32, 4, 7, 76, 194, 240, 156, 48, 8, 8, 119, 406, 666, 592, 300, 88, 8, 9, 176, 784, 1632, 1896, 1344, 576, 128, 16, 10, 249, 1416, 3648, 5344, 4904, 2848, 1024, 224, 16, 11, 340, 2418, 7584
Offset: 1

Views

Author

Clark Kimberling, Mar 02 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle T(n,k) given by (1, 1, -1, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 1, 1, -2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 16 2012

Examples

			First five rows:
  1;
  2,  1;
  3,  4,  2;
  4, 11, 10,  2;
  5, 24, 32, 16,  4;
First five polynomials v(n,x):
  1
  2 +   x
  3 +  4x +  2x^2
  4 + 11x + 10x^2 +  2x^3
  5 + 24x + 32x^2 + 16x^3 + 4x^4
From _Philippe Deléham_, Mar 16 2012: (Start)
(1, 1, -1, 1, 0, 0, ...) DELTA (0, 1, 1, -2, 0, 0, ...) begins:
  1;
  1,  0;
  2,  1,  0;
  3,  4,  2,  0;
  4, 11, 10,  2,  0;
  5, 24, 32, 16,  4,  0;
  6, 45, 84, 72, 32,  4,  0; (End)
		

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] + 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[%]    (* A208749 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208750 *)

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),
where u(1,x)=1, v(1,x)=1.
As DELTA-triangle with 0 <= k <= n: g.f.: (1-x+x^2-y*x^2-2*t^2*x^2)/(1-2*x+x^2-2*y*x^2-2*y^2*x^2). - Philippe Deléham, Mar 16 2012
As DELTA-triangle: T(n,k) = 2*T(n-1,k) - T(n-2,k) + 2*T(n-2,k-1) + 2*T(n-2,k-2), T(0,0) = T(1,0) = T(2,1) = 1, T(2,0) = 2, T(1,1) = T(2,2) = 0 and T(n,k) = 0 if k < 0 or if k > n. - Philippe Deléham, Mar 16 2012

A208751 Triangle of coefficients of polynomials u(n,x) jointly generated with A208752; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 6, 2, 1, 12, 12, 2, 1, 20, 40, 18, 2, 1, 30, 100, 86, 24, 2, 1, 42, 210, 294, 150, 30, 2, 1, 56, 392, 812, 656, 232, 36, 2, 1, 72, 672, 1932, 2268, 1240, 332, 42, 2, 1, 90, 1080, 4116, 6624, 5172, 2100, 450, 48, 2, 1, 110, 1650, 8052, 17028, 17996
Offset: 1

Views

Author

Clark Kimberling, Mar 01 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle T(n,k) given by (1, 0, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 2, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 17 2012

Examples

			First five rows:
  1;
  1,  2;
  1,  6,  2;
  1, 12, 12,  2;
  1, 20, 40, 18,  2;
First five polynomials u(n,x):
  1
  1 +  2x
  1 +  6x +  2x^2
  1 + 12x + 12x^2 +  2x^3
  1 + 20x + 40x^2 + 18x^3 + 2x^4
From _Philippe Deléham_, Mar 17 2012: (Start)
(1, 0, 1, 0, 0, ...) DELTA (0, 2, -1, 0, 0, ...) begins:
  1;
  1,   0;
  1,   2,   0;
  1,   6,   2,   0;
  1,  12,  12,   2,   0;
  1,  20,  40,  18,   2,   0;
  1,  30, 100,  86,  24,   2,   0; (End)
		

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_] := 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[%]    (* A208751 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208752 *)

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),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 17 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-x-y*x)/(1-2*x-y*x+x^2-y*x^2).
T(n,k) = 2*T(n-1,k) + T(n-1,k-1) - T(n-2,k) + T(n-2,k-1), T(0,0) = T(1,0) = T(2,0) = 1, T(1,1) = T(2,2) = 0, T(2,1) = 2 and T(n,k) = 0 if k < 0 or if k > n. (End)

A208752 Triangle of coefficients of polynomials v(n,x) jointly generated with A208751; see the Formula section.

Original entry on oeis.org

1, 2, 1, 3, 5, 1, 4, 14, 8, 1, 5, 30, 34, 11, 1, 6, 55, 104, 63, 14, 1, 7, 91, 259, 253, 101, 17, 1, 8, 140, 560, 806, 504, 148, 20, 1, 9, 204, 1092, 2178, 1966, 884, 204, 23, 1, 10, 285, 1968, 5202, 6412, 4090, 1420, 269, 26, 1, 11, 385, 3333, 11286, 18238
Offset: 1

Views

Author

Clark Kimberling, Mar 01 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (0, 2, -1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 1/2, -1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 17 2012
Setting v(0,x) = 0, the sequence of polynomials {v(n,x) : n >= 0} satisfies the second-order recurrence v(n,x) = (x + 2)*v(n-1,x) + (x - 1)*v(n-2,x) with v(0,x) = 0 and v(1,x) = 1. Then by Norfleet, this sequence of polynomials is a strong divisibility sequence of polynomials in the ring Z[x], that is gcd(v(n,x), v(m,x)) = v(gcd(n,m),x). In particular, if n divides m then v(n,x) divides v(m,x) in Z[x]. - Peter Bala, Feb 07 2024

Examples

			First five rows:
  1
  2   1
  3   5    1
  4   14   8    1
  5   30   34   11   1
First five polynomials u(n,x) - see A208751:
  1
  1 + 2*x
  1 + 6*x + 2*x^2
  1 + 12*x + 12*x^2 + 2*x^3
  1 + 20*x + 40*x^2 + 18*x^3 + 2*x^4
(0, 2, -1/2, 1/2, 0, 0, ...) DELTA (1, 0, 1/2, -1/2, 0, 0, ...) begins:
  1
  0, 1
  0, 2, 1
  0, 3, 5, 1
  0, 4, 14, 8, 1
  0, 5, 30, 34, 11, 1. - _Philippe Deléham_, Mar 17 2012
		

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_] := 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[%]    (* A208751 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208752 *)

Formula

u(n,x)=u(n-1,x)+2x*v(n-1,x),
v(n,x)=u(n-1,x)+(x+1)*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
T(n,k) = 2*T(n-1,k) + T(n-1,k-1) - T(n-2,k) + T(n-2,k-1), T(1,0) = 1, T(2,0) = 2, T(2,1) = 1, T(n,k) = 0 if k<0 or if k>=n. - Philippe Deléham, Mar 17 2012
G.f.: -x*y/(-1+2*x-x^2+x^2*y+x*y). - R. J. Mathar, Aug 12 2015

A208753 Triangle of coefficients of polynomials u(n,x) jointly generated with A208754; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 8, 1, 18, 4, 1, 32, 24, 1, 50, 80, 8, 1, 72, 200, 64, 1, 98, 420, 280, 16, 1, 128, 784, 896, 160, 1, 162, 1344, 2352, 864, 32, 1, 200, 2160, 5376, 3360, 384, 1, 242, 3300, 11088, 10560, 2464, 64, 1, 288, 4840, 21120, 28512, 11264, 896, 1
Offset: 1

Views

Author

Clark Kimberling, Mar 03 2012

Keywords

Comments

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

Examples

			First five rows:
1
1...2
1...8
1...18...4
1...32...24
First five polynomials u(n,x):
1
1 + 2x
1 + 8x
1 + 18x + 4x^2
1 + 32x + 24x^2
		

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_] := 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[%]    (* A208753 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208754 *)

Formula

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

A208754 Triangle of coefficients of polynomials v(n,x) jointly generated with A208753; see the Formula section.

Original entry on oeis.org

1, 3, 5, 2, 7, 10, 9, 28, 4, 11, 60, 28, 13, 110, 108, 8, 15, 182, 308, 72, 17, 280, 728, 352, 16, 19, 408, 1512, 1248, 176, 21, 570, 2856, 3600, 1040, 32, 23, 770, 5016, 8976, 4400, 416, 25, 1012, 8316, 20064, 14960, 2880, 64, 27, 1300, 13156, 41184
Offset: 1

Views

Author

Clark Kimberling, Mar 03 2012

Keywords

Comments

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

Examples

			First five rows:
1
3
5...2
7...10
9...28...4
First five polynomials v(n,x):
1
3
5 + 2x
7 + 10x
9 + 28x + 4x^2
		

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_] := 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[%]    (* A208753 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]    (* A208754 *)

Formula

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

A208758 Triangle of coefficients of polynomials v(n,x) jointly generated with A208757; see the Formula section.

Original entry on oeis.org

1, 0, 3, 0, 1, 8, 0, 1, 4, 22, 0, 1, 4, 16, 60, 0, 1, 4, 18, 56, 164, 0, 1, 4, 20, 68, 188, 448, 0, 1, 4, 22, 80, 248, 608, 1224, 0, 1, 4, 24, 92, 312, 864, 1920, 3344, 0, 1, 4, 26, 104, 380, 1152, 2928, 5952, 9136, 0, 1, 4, 28, 116, 452, 1472, 4128, 9696, 18192
Offset: 1

Views

Author

Clark Kimberling, Mar 02 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, 1/3, 2/3, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (3, -1/3, -2/3, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 02 2012

Examples

			First five rows:
  1;
  0,  3;
  0,  1,  8;
  0,  1,  4, 22;
  0,  1,  4, 16, 60;
First five polynomials v(n,x):
  1
     3x
      x + 8x^2
      x + 4x^2 + 22x^3
      x + 4x^2 + 16x^3 + 60^x4
		

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*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[%]  (* A208757 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]  (* A208758 *)

Formula

u(n,x) = u(n-1,x) + 2x*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.
As triangle T(n,k), 0 <= k <= n: g.f.: (1-x-y*x)/(1-(1+2*y)*x -2*y(y-1)*x^2). - Philippe Deléham, Mar 02 2012
As triangle T(n,k), 0 <= k <= n: T(n,k) = T(n-1,k) + 2*T(n-1,k-1) - 2*T(n-2,k-1) + 2*T(n-2,k-2) with T(0,0) = 1, T(1,0) = 0, T(1,1) = 3 and T(n,k) = 0 if k < 0 or if k > n. - Philippe Deléham, Mar 02 2012

A208759 Triangle of coefficients of polynomials u(n,x) jointly generated with A208760; see the Formula section.

Original entry on oeis.org

1, 1, 2, 1, 4, 6, 1, 6, 16, 16, 1, 8, 30, 56, 44, 1, 10, 48, 128, 188, 120, 1, 12, 70, 240, 504, 608, 328, 1, 14, 96, 400, 1080, 1872, 1920, 896, 1, 16, 126, 616, 2020, 4512, 6672, 5952, 2448, 1, 18, 160, 896, 3444, 9352, 17856, 23040, 18192, 6688, 1, 20, 198, 1248, 5488, 17472, 40600, 67776, 77616, 54976, 18272
Offset: 1

Views

Author

Clark Kimberling, Mar 02 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 2, 1, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 18 2012

Examples

			First five rows:
  1;
  1,  2;
  1,  4,  6;
  1,  6, 16, 16;
  1,  8, 30, 56, 44;
First five polynomials u(n,x):
  1
  1 + 2x
  1 + 4x +  6x^2
  1 + 6x + 16x^2 + 16x^3
  1 + 8x + 30x^2 + 56x^3 + 44x^4
From _Philippe Deléham_, Mar 18 2012: (Start)
(1, 0, 0, 0, 0, ...) DELTA (0, 2, 1, -1, 0, 0, ...) begins:
  1;
  1,   0;
  1,   2,   0;
  1,   4,   6,   0;
  1,   6,  16,  16,   0;
  1,   8,  30,  56,  44,   0;
  1,  10,  48, 128, 188, 120,  0; (End)
		

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] + 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[%]  (* A208759 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]  (* A208760 *)
    Rest[CoefficientList[CoefficientList[Series[(1-2*y*x-2*y^2*x^2)/(1-x-2*y*x- 2*y^2*x^2), {x,0,20}, {y,0,20}], x], y]//Flatten] (* G. C. Greubel, Mar 28 2018 *)

Formula

u(n,x) = u(n-1,x) + 2*x*v(n-1,x),
v(n,x) = (x+1)*u(n-1,x) + 2*x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 18 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-2y*x-2*y^2*x^2)/(1-x-2*y*x-2*y^2*x^2).
T(n,k) = T(n-1,k) + 2*T(n-1,k-1) + 2*T(n-2,k-2), T(0,0) = T(1,0) = T(2,0) = 1, T(1,1) = T(2,2) = 0, T(2,1) = 2 and T(n,k) = 0 if k < 0 or if k > n. (End)

Extensions

Terms a(58) onward added by G. C. Greubel, Mar 28 2018

A208760 Triangle of coefficients of polynomials v(n,x) jointly generated with A208759; see the Formula section.

Original entry on oeis.org

1, 1, 3, 1, 5, 8, 1, 7, 20, 22, 1, 9, 36, 72, 60, 1, 11, 56, 158, 244, 164, 1, 13, 80, 288, 632, 796, 448, 1, 15, 108, 470, 1320, 2376, 2528, 1224, 1, 17, 140, 712, 2420, 5592, 8544, 7872, 3344, 1, 19, 176, 1022, 4060, 11372, 22368, 29712, 24144, 9136
Offset: 1

Views

Author

Clark Kimberling, Mar 02 2012

Keywords

Comments

For a discussion and guide to related arrays, see A208510.
Subtriangle of the triangle given by (1, 0, -1/3, 1/3, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 3, -1/3, -2/3, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 18 2012

Examples

			First five rows:
  1;
  1,  3;
  1,  5,  8;
  1,  7, 20, 22;
  1,  9, 36, 72, 60;
First five polynomials v(n,x):
  1
  1 + 3x
  1 + 5x +  8x^2
  1 + 7x + 20x^2 + 22x^3
  1 + 9x + 36x^2 + 72x^3 + 60x^4
From _Philippe Deléham_, Mar 18 2012: (Start)
(1, 0, -1/3, 1/3, 0, 0, ...) DELTA (0, 3, -1/3, -2/3, 0, 0, ...) begins:
  1;
  1,   0;
  1,   3,   0;
  1,   5,   8,   0;
  1,   7,  20,  22,   0;
  1,   9,  36,  72,  60,   0;
  1,  11,  56, 158, 244, 164,  0; (End)
		

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] + 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[%]  (* A208759 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]  (* A208760 *)

Formula

u(n,x) = u(n-1,x) + 2x*v(n-1,x),
v(n,x) = (x+1)*u(n-1,x) + 2x*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
From Philippe Deléham, Mar 18 2012: (Start)
As DELTA-triangle with 0 <= k <= n:
G.f.: (1-2*y*x+y*x^2-2*y^2*x^2)/(1-x-2*y*x-2*y^2*x^2).
T(n,k) = T(n-1,k) + 2*T(n-1,k-1) + 2*T(n-2,k-2), T(0,0) = T(1,0) = T(2,0) = 1, T(1,1) = T(2,2) = 0, T(2,1) = 3 and T(n,k) = 0 if k < 0 or if k > n. (End)
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