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 A047071 Array T by antidiagonals: 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=3x unless x=0 or x=h. 0
 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 3, 3, 1, 1, 1, 3, 6, 4, 1, 1, 2, 3, 9, 10, 5, 1, 1, 3, 3, 12, 19, 15, 6, 1, 1, 4, 6, 15, 31, 34, 21, 7, 1, 1, 5, 4, 15, 46, 65, 55, 28, 8, 1, 1, 6, 9, 15, 61, 111, 120, 83, 36, 9, 1, 1, 7, 15, 15, 76, 172, 231, 203, 119, 45 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,9 LINKS EXAMPLE Antidiagonals (beginning on row 0): {1}; {1,1}; {1,1,1}; {1,1,2,1}; {1,2,3,3,1}; ... CROSSREFS Sequence in context: A054991 A302918 A316149 * A124287 A253240 A290472 Adjacent sequences:  A047068 A047069 A047070 * A047072 A047073 A047074 KEYWORD nonn,tabl AUTHOR STATUS approved

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Last modified September 29 16:13 EDT 2020. Contains 337432 sequences. (Running on oeis4.)