%I A108756
%S A108756 1,1,1,1,1,1,2,3,1,1,1,4,5,1,1,3,6,6,7,1,1,1,10,15,8,9,1,1,4,10,21,28,
%T A108756 10,11,1,1,1,20,35,36,45,12,13,1,1,5,15,56,84,55,66,14,15,1,1,1,35,70,
%U A108756 120,165,78,91,16,17,1,1,6,21,126,210,220,286,105,120,18,19,1,1,1,56
%N A108756 A triangle related to the Jacobsthal polynomials.
%C A108756 Riordan array ((1+x-x^2)/(1-x^2)^2, x/(1-x^2)^2). Row sums are A108742. 
               Diagonal sums are F(n+1). Corresponding diagonals triangle is A102426.
%H A108756 D. Stutson, V. Kocic and G. Arora, <a href="http://www.xula.edu/math/
               Research/TR/SKA1.pdf">A Few Identities involving Jacobsthal polynomials</
               a>.
%F A108756 Number triangle T(n, k)=binomial(floor((n+k+1)/2)+k, floor((n+k)/2-k)
%e A108756 Rows begin
%e A108756 1;
%e A108756 1,1;
%e A108756 1,1,1;
%e A108756 2,3,1,1;
%e A108756 1,4,5,1,1;
%e A108756 3,6,6,7,1,1;
%e A108756 1,10,15,8,9,1,1;
%Y A108756 Sequence in context: A094006 A140188 A140737 this_sequence A106178 A108714 
               A135508
%Y A108756 Adjacent sequences: A108753 A108754 A108755 this_sequence A108757 A108758 
               A108759
%K A108756 easy,nonn,tabl
%O A108756 0,7
%A A108756 Paul Barry (pbarry(AT)wit.ie), Jun 22 2005