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Antidiagonal sums of the second quadrant of array A(k,m) = F_k(m), F_k(m) being the k-th Fibonacci polynomial evaluated at m.
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%I #18 Jun 02 2018 14:18:35

%S 0,1,1,1,1,1,0,2,1,-10,39,-58,-166,1611,-6311,10083,54195,-565257,

%T 2727568,-6102368,-26464605,394614352,-2515452801,8797315672,

%U 11441288836,-458369484247,4097437715969,-21769011878335,36715605929957,703213495381553,-10042075731879152

%N Antidiagonal sums of the second quadrant of array A(k,m) = F_k(m), F_k(m) being the k-th Fibonacci polynomial evaluated at m.

%C Equivalently, antidiagonal sums of the fourth quadrant of array A(k,m).

%H Alois P. Heinz, <a href="/A304359/b304359.txt">Table of n, a(n) for n = 0..616</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Fibonacci_polynomials">Fibonacci polynomials</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Quadrant_(plane_geometry)">Quadrant (plane geometry)</a>

%F a(n) = Sum_{j=0..n} F_j(j-n).

%p F:= (n, k)-> (<<0|1>, <1|k>>^n)[1, 2]:

%p a:= n-> add(F(-j, n-j), j=0..n):

%p seq(a(n), n=0..30);

%p # second Maple program:

%p F:= proc(n, k) option remember;

%p `if`(n<2, n, k*F(n-1, k)+F(n-2, k))

%p end:

%p a:= n-> add(F(j, j-n), j=0..n):

%p seq(a(n), n=0..30);

%p # third Maple program:

%p a:= n-> add(combinat[fibonacci](j, j-n), j=0..n):

%p seq(a(n), n=0..30);

%t a[n_] := Sum[Fibonacci[j, j - n], {j, 0, n}];

%t Table[a[n], {n, 0, 30}] (* _Jean-François Alcover_, Jun 02 2018, from 3rd Maple program *)

%Y Cf. A000045, A084844, A304357.

%K sign

%O 0,8

%A _Alois P. Heinz_, May 11 2018