a(n) is the total number of paths starting at (0, 0), ending at (n, 0), consisting of steps (1, 1), (1, 0), (1, -2), and staying on or above y = -3.
A379462
a(n) is the total number of paths starting at (0, 0), ending at (n, 0), consisting of steps (1, 1), (1, 0), (1, -2), and staying on or above y = -3.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =4a(4) =13a(5) =31a(6) =75a(7) =204a(8) =561a(9) =1499a(10) =4001a(11) =10814a(12) =29364a(13) =79704a(14) =216672a(15) =590764a(16) =1614421a(17) =4419049a(18) =12116139a(19) =33277722a(20) =91546143a(21) =252209535a(22) =695803659a(23) =1922166420a(24) =5316714156a(25) =14723570406a(26) =40820144106a(27) =113293243636a(28) =314759548879a(29) =875342190283
External references
- oeis: A379462