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

1, 2, 2, 2, 5, 4, 2, 9, 15, 8, 2, 13, 33, 37, 16, 2, 17, 59, 103, 91, 32, 2, 21, 93, 221, 297, 213, 64, 2, 25, 135, 407, 739, 807, 491, 128, 2, 29, 185, 677, 1553, 2285, 2105, 1109, 256, 2, 33, 243, 1047, 2907, 5391, 6675, 5319, 2475, 512, 2, 37, 309, 1533

Offset: 1

Author

Clark Kimberling, Mar 04 2012

Keywords

• nonn
• tabl

Comments

Alternating row sums: 1,0,1,0,1,0,1,0,1,0,1,0,...

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

Examples

			First five rows:
1
2...2
2...5....4
2...9...15...8
2...13...33...37...16
First five polynomials v(n,x):
1
2 + 2x
2 + 5x + 4x^2
2 + 9x + 15x^2 + 8x^3
2 + 13x + 33x^2 + 37x^3 + 16x^4
		

Crossrefs

Cf. A208923, A208510.

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.