%I A105868
%S A105868 1,0,1,0,2,1,0,0,6,1,0,0,6,12,1,0,0,0,30,20,1,0,0,0,20,90,30,1,0,0,0,0,
%T A105868 140,210,42,1,0,0,0,0,70,560,420,56,1,0,0,0,0,0,630,1680,756,72,1,0,0,
               0,
%U A105868 0,0,252,3150,4200,1260,90,1,0,0,0,0,0,0,2772,11550,9240,1980,110,1,0,
               0
%N A105868 Number triangle C(n,k)C(k,n-k).
%C A105868 Row sums are the central trinomial coefficients A002426. Diagonal sums 
               are A105869.
%C A105868 Product of A007318 and this sequence is A008459.
%C A105868 Coefficient array for polynomials P(n,x)=x^n*F(1/2-n/2,-n/2;1;4/x). [From 
               Paul Barry (pbarry(AT)wit.ie), Oct 04 2008]
%e A105868 Triangle begins
%e A105868 1;
%e A105868 0,1;
%e A105868 0,2,1;
%e A105868 0,0,6,1;
%e A105868 0,0,6,12,1;
%e A105868 0,0,0,30,20,1;
%Y A105868 Cf. A063007, A105870.
%Y A105868 Sequence in context: A136129 A034093 A057150 this_sequence A057275 A057271 
               A021480
%Y A105868 Adjacent sequences: A105865 A105866 A105867 this_sequence A105869 A105870 
               A105871
%K A105868 easy,nonn,tabl
%O A105868 0,5
%A A105868 Paul Barry (pbarry(AT)wit.ie), Apr 23 2005