Number of Dyck paths of semilength n with no peaks at height 0 (mod 3) and no valleys at height 2 (mod 3).
A152225
Number of Dyck paths of semilength n with no peaks at height 0 (mod 3) and no valleys at height 2 (mod 3).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =22a(6) =56a(7) =146a(8) =388a(9) =1048a(10) =2869a(11) =7942a(12) =22192a(13) =62510a(14) =177308a(15) =506008a(16) =1451866a(17) =4185788a(18) =12119696a(19) =35227748a(20) =102753800a(21) =300672368a(22) =882373261a(23) =2596389190a(24) =7658677856a(25) =22642421206a(26) =67081765932a(27) =199128719896a(28) =592179010350
External references
- oeis: A152225