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A208753
Triangle of coefficients of polynomials u(n,x) jointly generated with A208754; see the Formula section.
3
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
1,3
COMMENTS
For a discussion and guide to related arrays, see A208510.
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.
EXAMPLE
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
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 *)
CROSSREFS
Sequence in context: A009385 A008308 A176889 * A118931 A101280 A321280
KEYWORD
nonn,tabf
AUTHOR
Clark Kimberling, Mar 03 2012
STATUS
approved