A118243 Triangle generated from Pell polynomials.

1, 1, 2, 1, 3, 5, 1, 4, 10, 12, 1, 5, 17, 33, 29, 1, 6, 26, 72, 109, 70, 1, 7, 37, 135, 305, 360, 169, 1, 8, 50, 228, 701, 1292, 1189, 408, 1, 9, 65, 357, 1405, 3640, 5473, 3927, 985, 1, 10, 82, 528, 2549, 8658, 18901, 23184, 12970, 2378, 1, 11, 101, 747, 4289

Offset: 0

Author

Gary W. Adamson, Apr 17 2006

Keywords

• nonn
• tabl

Comments

a(k)/a(k-1) of the array sequences tend to exp(arcsinh(N/2)) with rows starting N = 2, 3, 4, .... For example, terms of the Pell sequence row N=2 tend to converge to 2.414... = 1 + sqrt(2).

For scalar s, let V_m(s) be polynomials defined by V_0(s)=1, V_1(s)=s and V_m(s)=s*V_{m-1}(s)+V_{m-2}(s) (m>1). Then the generating array A (not the triangle) in the example below is given identically by the infinite matrix A=(A_{r,c}) with entries A_{r,c}=V_c(r+2); r=0,1,2,...; c=0,1,2,.... - L. Edson Jeffery, Aug 14 2011

Examples

			First few rows of the triangle:
  1;
  1, 2;
  1, 3,  5;
  1, 4, 10, 12;
  1, 5, 17, 33,  29;
  1, 6, 26, 72, 109, 70;
  ...
Deleting first row of the A073133 array, the generating array of the triangle is
  1, 2,  5,  12,  29, ...
  1, 3, 10,  33, 109, ...
  1, 4, 17,  72, 305, 1292, ...
  1, 5, 26, 135, 701, 3640, ...
  ...
By rows starting N = 2,3,... the generators of the array are a(k) = N(k-1)+ (k-2) (a generalized Fibonacci operation). Thus row (N=3) = 1, 3, 10, 33, ...
Columns of the array are generated from the terms of A038137 considered as Pell polynomials (analogous to the Fibonacci polynomials):
(1); (x + 1); (x^2 + 2x + 2); (x^3 + 3x^2 + 5x + 3); (x^4 + 4x^3 + 9x^2 + 10x + 5); and so on, where coefficient sums = the Pell numbers (1, 2, 5, 12, 29, ...).
k-th column of the triangle (offset T(0,0)) is generated from f(x), k-th degree Pell polynomial. For example, T(4,3)= 33, = f(2) using x^3 + 3x^2 + 5x + 3 = (8+12+10+3) = 33.
		

Crossrefs

Cf. A073133, A038137.

Formula

Triangle, antidiagonals of the array in A073133, deleting the first row (Fibonacci numbers). Columns are generated as f(x) from the Pell polynomials (analogous to the Fibonacci polynomials).