A208331 Triangle of coefficients of polynomials v(n,x) jointly generated with A208330; see the Formula section.
1, 1, 3, 1, 6, 5, 1, 9, 15, 11, 1, 12, 30, 44, 21, 1, 15, 50, 110, 105, 43, 1, 18, 75, 220, 315, 258, 85, 1, 21, 105, 385, 735, 903, 595, 171, 1, 24, 140, 616, 1470, 2408, 2380, 1368, 341, 1, 27, 180, 924, 2646, 5418, 7140, 6156, 3069, 683, 1, 30, 225
Offset: 1
Examples
First five rows: 1 1...3 1...6...5 1...9...15...11 1...12...30...44...21 First five polynomials u(n,x): 1, 1 + 3x, 1 + 6x + 5x^2, 1 + 9x + 15x^2 + 11x^3, 1+12x + 30x^2 + 44x^3 + 21x^4. (1, 0, 0, 1, 0, 0, ...) DELTA (0, 3, -4/3, -2/3, 0, 0, ...) begins : 1 1, 0 1, 3, 0 1, 6, 5, 0 1, 9, 15, 11, 0 1, 12, 30, 44, 21, 0. - _Philippe Deléham_, Mar 18 2012
Crossrefs
Cf. A208330.
Programs
-
Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 13; u[n_, x_] := u[n - 1, x] + x*v[n - 1, x]; v[n_, x_] := 2 x*u[n - 1, x] + (x + 1)*v[n - 1, x]; 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[%] (* A208330 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A208331 *)
Formula
u(n,x)=u(n-1,x)+x*v(n-1,x),
v(n,x)=2x*u(n-1,x)+(x+1)*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
T(n,k) = A001045(n+2)*binomial(n-1,k). - Philippe Deléham, Mar 18 2012
T(n,k) = 2*T(n-1,k) + T(n-1,k-1) - T(n-2,k) - T(n-2,k-1) + 2*T(n-2,k-2), T(1,0) = T(2,0) = 1, T(2,1) = 3 and T(n,k) = 0 if k<0 or if k>=n. - Philippe Deléham, Mar 18 2012
Comments