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Riordan array (1/(1-2x), x/((1-x)(1-2x))).
1

%I #5 Jan 17 2014 09:02:23

%S 1,2,1,4,5,1,8,17,8,1,16,49,39,11,1,32,129,150,70,14,1,64,321,501,338,

%T 110,17,1,128,769,1524,1375,640,159,20,1,256,1793,4339,4973,3075,1083,

%U 217,23,1,512,4097,11762,16508

%N Riordan array (1/(1-2x), x/((1-x)(1-2x))).

%C Row sums are A007052. Diagonal sums are F(2n+1)=A001519(n+1)=A122367(n). Product of A007318 and Delannoy triangle A008288.

%F Number triangle T(n,k)=sum{j=0..n-k, C(n-j,k)C(n+k,j)}

%F T(n,k) = 3*T(n-1,k) + T(n-1,k-1) - 2*T(n-2,k), T(0,0) = T(1,1) = 1, T(1,0) = 2, T(n,k) = 0 if k<0 or if k>n. - _Philippe Deléham_, Jan 17 2014

%e Triangle begins

%e 1,

%e 2, 1,

%e 4, 5, 1,

%e 8, 17, 8, 1,

%e 16, 49, 39, 11, 1,

%e 32, 129, 150, 70, 14, 1

%K easy,nonn,tabl

%O 0,2

%A _Paul Barry_, Oct 22 2006