A209768 Triangle of coefficients of polynomials v(n,x) jointly generated with A209767; see the Formula section.

1, 2, 3, 3, 7, 7, 4, 14, 26, 17, 5, 24, 64, 83, 41, 6, 37, 130, 251, 250, 99, 7, 53, 233, 599, 899, 723, 239, 8, 72, 382, 1232, 2478, 3022, 2034, 577, 9, 94, 586, 2282, 5774, 9476, 9700, 5607, 1393, 10, 119, 854, 3908, 11952, 24734, 34152, 30063

Offset

1,2

Comments

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

Links

Table of n, a(n) for n=1..53.

Formula

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

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

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

Example

First five rows:
1
2...3
3...7....7
4...14...26...17
5...24...64...83...41
First three polynomials v(n,x): 1, 2 + 3x , 3 + 7x + 7x^2.

Mathematica

u[1, x_] := 1; v[1, x_] := 1; z = 16;
u[n_, x_] := x*u[n - 1, x] + (x + 1)*v[n - 1, x];
v[n_, x_] := 2 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[%]    (* A209767 *)
Table[Expand[v[n, x]], {n, 1, z}]
cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
TableForm[cv]
Flatten[%]    (* A209768 *)

Crossrefs

Cf. A209667, A208510.

Sequence in context: A210558 A208920 A210234 * A209169 A222294 A181850

Adjacent sequences: A209765 A209766 A209767 * A209769 A209770 A209771

Keyword

nonn,tabl

Author

Clark Kimberling, Mar 15 2012

Status

approved