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A210214
Triangle of coefficients of polynomials v(n,x) jointly generated with A210213; see the Formula section.
3
1, 3, 1, 6, 5, 1, 11, 14, 7, 1, 19, 34, 25, 9, 1, 32, 74, 75, 39, 11, 1, 53, 152, 195, 139, 56, 13, 1, 87, 299, 468, 419, 231, 76, 15, 1, 142, 571, 1056, 1147, 791, 356, 99, 17, 1, 231, 1066, 2280, 2911, 2429, 1364, 519, 125, 19, 1, 375, 1956, 4755, 6991
OFFSET
1,2
COMMENTS
For a discussion and guide to related arrays, see A208510.
FORMULA
u(n,x)=x*u(n-1,x)+v(n-1,x)+1,
v(n,x)=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
3....1
6....5....1
11...14...7....1
19...34...25...9...1
First three polynomials v(n,x): 1, 3 + x , 6 + 5x + x^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] + (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[%] (* A210213 *)
Table[Expand[v[n, x]], {n, 1, z}]
cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
TableForm[cv]
Flatten[%] (* A210214 *)
CROSSREFS
Sequence in context: A355010 A153641 A133545 * A322427 A209149 A343062
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Mar 19 2012
STATUS
approved