A047050 Array T read 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 step touches the line y=4x/3 unless x=0 or x=h.

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 2, 3, 1, 1, 3, 2, 5, 4, 1, 1, 4, 5, 5, 9, 5, 1, 1, 5, 9, 10, 14, 14, 6, 1, 1, 6, 14, 9, 14, 28, 20, 7, 1, 1, 7, 20, 23, 14, 42, 48, 27, 8, 1, 1, 8, 27, 43, 23, 56, 90, 75, 35, 9, 1, 1, 9, 35, 70, 66, 56, 146, 165, 110, 44

Offset

0,9

Links

Table of n, a(n) for n=0..75.

Example

Diagonals (beginning on row 0): {1}; {1,1}; {1,1,1}; {1,1,2,1}; ...

Crossrefs

Mirror image of A047040.

Sequence in context: A276605 A047060 A050167 * A205028 A325055 A325526

Adjacent sequences: A047047 A047048 A047049 * A047051 A047052 A047053

Keyword

nonn,tabl

Author

Clark Kimberling

Status

approved