%I #6 Jan 04 2014 19:49:18
%S 1,-3,1,7,-6,1,-15,23,-9,1,31,-72,48,-12,1,-63,201,-198,82,-15,1,127,
%T -522,699,-420,125,-18,1,-255,1291,-2223,1795,-765,177,-21,1,511,
%U -3084,6562,-6768,3840,-1260,238,-24,1,-1023,7181,-18324,23276,-16758,7266,-1932,308,-27,1,2047,-16398,49029,-74616,65870
%N Riordan array (1/(1+3x+2x^2),x/(1+3x+2x^2)).
%C Signed version of A110441. Factors as (1/(1+x),x/(1+x))*((1-x)/(1+x),x(1-x)/(1+x)), or inverse binomial transform of A080246. Inverse of little Schroeder number array A110440. Row sums are A108520. Diagonal sums are (-1)^n*A001906(n+1).
%F T(n,k)=-3*T(n-1,k)+T(n-1,k-1)-2*T(n-2,k), T(0,0)=1, T(n,k)=0 if k<0 or if k>n. - _Philippe Deléham_, Jan 04 2013
%e Triangle starts
%e 1;
%e -3,1;
%e 7,-6,1;
%e -15,23,-9,1;
%e 31,-72,48,-12,1;
%K easy,sign,tabl
%O 0,2
%A _Paul Barry_, Aug 18 2005