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Generalized Riordan array (1,x)+(x,x^2)+(x^2,x^3).
2

%I #3 Mar 30 2012 18:59:14

%S 1,1,1,1,0,1,0,1,0,1,0,0,0,0,1,0,1,1,0,0,1,0,0,0,0,0,0,1,0,0,0,1,0,0,

%T 0,1,0,0,1,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,

%U 0,1,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,1

%N Generalized Riordan array (1,x)+(x,x^2)+(x^2,x^3).

%C Row sums are A083039. Diagonal sums are A117199. Inverse is A117200.

%F Number triangle T(n,k)=if(n=k,1,0) OR if(n=2k+1,1,0) OR if(n=3k+2,1,0).

%e Triangle begins

%e 1,

%e 1, 1,

%e 1, 0, 1,

%e 0, 1, 0, 1,

%e 0, 0, 0, 0, 1,

%e 0, 1, 1, 0, 0, 1,

%e 0, 0, 0, 0, 0, 0, 1,

%e 0, 0, 0, 1, 0, 0, 0, 1,

%e 0, 0, 1, 0, 0, 0, 0, 0, 1,

%e 0, 0, 0, 0, 1, 0, 0, 0, 0, 1,

%e 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1

%K easy,nonn,tabl

%O 0,1

%A _Paul Barry_, Mar 02 2006