%I #5 Mar 31 2012 13:20:06
%S 1,1,1,1,1,1,1,6,-15,20,-15,6,-1,5,-9,5,5,-9,5,-1,4,-3,-10,25,-24,11,
%T -2,3,3,-25,45,-39,17,-3,2,9,-40,65,-54,23,-4,1,15,-55,85,-69,29,-5,
%U 21,-70,105,-84,35,-6,15,-19,-95,396,-751,917,-792,495,-220
%N Coefficient array for certain numerator polynomials N7(n,x), n >= 0 (rising powers of x).
%C The g.f. of column k of array A063265(n,k) is (x^(ceiling(k/6)))*N7(k,x)/(1-x)^(k+1).
%C The degree sequence for the polynomials N7(n,x) is [0,0,0,0,0,0,0,5,6,6,6,6,6,5,11,...].
%C All row sums N7(n,1)= 1.
%F a(n, m)=[x^m]N7(n, x), n, m >= 0, with N7(n, x) = sum(((1-x)^(j-1))*(x^(b(c(n), j)))*N7(n-j, x), j=1..6), N7(n, x)= 1 for n=0..6 and b(c(n), j) := 1 if 1<= j <= c(n) else 0, with c(n) := 5 if mod(n, 6)=0 and c(n) := mod(n, 6)-1 else; hence b(0, j)=0, j=1..6.
%e {1}; {1}; {1}; {1}; {1}; {1}; {1}; {6, -15, 20, -15, 6, -1}; {5, -9, 5, 5, -9, 5, -1}; ...
%e c=3: b(3,1)=b(3,2)=b(3,3)=1, b(3,j)=0 for j=4,5,6.
%e N7(8,x)= 5-9*x+5*x^2+5*x^3-9*x^4+5*x^5-x^6.
%K sign,easy,tabf
%O 0,8
%A _Wolfdieter Lang_, Jul 24 2001
|