Number of 4-Motzkin paths of length n with no level steps at odd level.
A257388
Number of 4-Motzkin paths of length n with no level steps at odd level.
Terms
- a(0) =1a(1) =4a(2) =17a(3) =72a(4) =306a(5) =1304a(6) =5573a(7) =23888a(8) =102702a(9) =442904a(10) =1915978a(11) =8314480a(12) =36195236a(13) =158067312a(14) =692475053a(15) =3043191200a(16) =13415404246a(17) =59321085720a(18) =263100680926
External references
- oeis: A257388