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Array T by diagonals: T(h,k)=number of paths consisting of steps from (0,0) to (h,k) such that each step has length 1 directed up or right and no right-step crosses the line y=3x/2. (Thus a path crosses the line only at lattice points and on up-steps.).
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%I #3 Mar 30 2012 18:57:06

%S 1,1,1,1,1,1,1,2,2,1,1,3,2,3,1,1,4,5,5,4,1,1,5,9,10,9,5,1,1,6,14,10,

%T 19,14,6,1,1,7,20,24,29,33,20,7,1,1,8,27,44,29,62,53,27,8,1,1,9,35,71,

%U 73,91,115,80,35,9,1,1,10,44,106,144,164,206,195,115,44,10,1,1,11,54,150

%N Array T by diagonals: T(h,k)=number of paths consisting of steps from (0,0) to (h,k) such that each step has length 1 directed up or right and no right-step crosses the line y=3x/2. (Thus a path crosses the line only at lattice points and on up-steps.).

%C T = transpose of A047110.

%e Northwest corner:

%e 1 1 1 1 1 1

%e 1 1 2 3 4 5

%e 1 2 2 5 9 14

%e 1 3 5 10 10 24

%e 1 4 9 19 29 29

%Y Cf. A047110.

%K nonn,tabl

%O 0,8

%A _Clark Kimberling_, Dec 08 2006