Number of set partitions with at most 3 blocks; number of Dyck paths of height at most 4; dimension of space of symmetric polynomials in 3 noncommuting variables.
A124302
Number of set partitions with at most 3 blocks; number of Dyck paths of height at most 4; dimension of space of symmetric polynomials in 3 noncommuting variables.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =14a(5) =41a(6) =122a(7) =365a(8) =1094a(9) =3281a(10) =9842a(11) =29525a(12) =88574a(13) =265721a(14) =797162a(15) =2391485a(16) =7174454a(17) =21523361a(18) =64570082a(19) =193710245a(20) =581130734a(21) =1743392201a(22) =5230176602a(23) =15690529805a(24) =47071589414a(25) =141214768241a(26) =423644304722
External references
- oeis: A124302