A210212 Triangle of coefficients of polynomials v(n,x) jointly generated with A210211; see the Formula section.

1, 2, 2, 3, 5, 4, 4, 10, 11, 8, 5, 16, 28, 23, 16, 6, 24, 51, 72, 47, 32, 7, 33, 90, 144, 176, 95, 64, 8, 44, 138, 294, 377, 416, 191, 128, 9, 56, 208, 492, 878, 938, 960, 383, 256, 10, 70, 290, 830, 1577, 2462, 2251, 2176, 767, 512, 11, 85, 400, 1250, 2952

Offset

1,2

Comments

First and last terms of row n: n and 2^(n-1)

Alternating row sums are signed products of two Fibonacci numbers.

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

Links

Table of n, a(n) for n=1..60.

Formula

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

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

where u(1,x)=1, v(1,x)=1.

Example

First five rows:
1
2...2
3...5...4
4...10...11...8
5...16...28...23...16
First three polynomials v(n,x): 1, 2 + 2x , 3 + 5x + 4x^2.

Mathematica

u[1, x_] := 1; v[1, x_] := 1; z = 16;
u[n_, x_] := x*u[n - 1, x] + v[n - 1, x] + 1;
v[n_, x_] := u[n - 1, x] + 2 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[%]    (* A210211 *)
Table[Expand[v[n, x]], {n, 1, z}]
cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
TableForm[cv]
Flatten[%]    (* A210212 *)

Crossrefs

Cf. A210211, A208510.

Sequence in context: A282443 A210554 A208912 * A209762 A026408 A301790

Adjacent sequences: A210209 A210210 A210211 * A210213 A210214 A210215

Keyword

nonn,tabl

Author

Clark Kimberling, Mar 19 2012

Status

approved