The number of endomorphisms of the symmetric inverse monoid on the set {1..n}.
A226466
The number of endomorphisms of the symmetric inverse monoid on the set {1..n}.
Terms
- a(0) =1a(1) =3a(2) =14a(3) =54a(4) =306a(5) =918a(6) =4524a(7) =25560a(8) =168828a(9) =1315764a(10) =11998584a(11) =125358192a(12) =1466062200a(13) =18835528104a(14) =262376016912
External references
- oeis: A226466