Number of peaks of the form ud in all paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1), U=(1,2), or d=(1,-1).
A108448
Number of peaks of the form ud in all paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1), U=(1,2), or d=(1,-1).
Terms
- a(0) =1a(1) =7a(2) =61a(3) =575a(4) =5641a(5) =56695a(6) =579125a(7) =5984767a(8) =62390545a(9) =654862247a(10) =6911195501a(11) =73265596607a(12) =779594526361
External references
- oeis: A108448