|
%I #5 Oct 02 2013 16:26:13
%S 1,2,1,3,5,2,4,7,7,3,5,9,10,12,5,6,11,13,17,19,8,7,13,16,22,27,31,13,
%T 8,15,19,27,35,44,50,21,9,17,22,32,43,57,71,81,34,10,19,25,37,51,70,
%U 92,115,131,55,11,21,28,42,59,83,113,149,186,212,89,12,23,31,47
%N Triangular array U(n,k) of coefficients of polynomials defined in Comments.
%C Polynomials u(n,k) are defined by u(n,x)=x*u(n-1,x)+(x^2)*u(n-2,x)+n*(x+1), where u(1)=1 and u(2,x)=x+2. The array (U(n,k)) is defined by rows:
%C u(n,x)=U(n,1)+U(n,2)*x+...+U(n,n-1)*x^(n-1).
%C In each column, the first number is a Fibonacci number and, with one exception, the difference between each two consecutive terms is a Fibonacci number (see the Formula section).
%C Alternating row sums: 1,1,0,1,-2,3,-5,8,-13,21,... (signed Fibonacci numbers)
%F Column k consists of the partial sums of the following sequence: F(k), F(k+2)+F(k-3), F(k+1), F(k+1), F(k+1),..., where F=000045 (Fibonacci numbers. That is, U(n+1,k)-U(n,k)=F(k+1) for n>1.
%e First six rows:
%e 1
%e 2...1
%e 3...5....2
%e 4...7....7....3
%e 5...9....10...12...5
%e 6...11...13...17...19...8
%e First three polynomials u(n,x): 1, 2 + x, 3 + 5x + 2x^2.
%t u[1, x_] := 1; u[2, x_] := x + 2; z = 14;
%t u[n_, x_] := x*u[n - 1, x] + (x^2)*u[n - 2, x] + n*(x + 1);
%t Table[Expand[u[n, x]], {n, 1, z/2}]
%t cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
%t TableForm[cu]
%t Flatten[%] (* A210880 *)
%Y Cf. A208510, A210881, A210874, A210875.
%K nonn,tabl
%O 1,2
%A _Clark Kimberling_, Mar 30 2012
|
