A145602 - cp's OEIS frontend

A145602 a(n) is the number of walks from (0,0) to (0,3) that remain in the upper half-plane y >= 0 using 2*n +1 unit steps either up (U), down (D), left (L) or right (R).

n	a(n)
1	1
2	24
3	392
4	5760
5	81675
6	1145144
7	16032016
8	225059328
9	3173688180
10	44986664800
11	641087516256
12	9183622822400
13	132211882468575
14	1912322889603000
15	27781440618420000
16	405248874740582400
17	5933888308457316900

[1, 24, 392, 5760, 81675, 1145144, 16032016, 225059328, 3173688180, 44986664800, 641087516256, 9183622822400, 132211882468575, 1912322889603000, 27781440618420000, 405248874740582400, 5933888308457316900]

cp's OEIS Frontend

A145602 a(n) is the number of walks from (0,0) to (0,3) that remain in the upper half-plane y >= 0 using 2*n +1 unit steps either up (U), down (D), left (L) or right (R).

Table of values

List of values