Number of endofunctions on [2n] such that the minimal cardinality of the nonempty preimages equals n.
A273325
Number of endofunctions on [2n] such that the minimal cardinality of the nonempty preimages equals n.
Terms
- a(0) =1a(1) =2a(2) =36a(3) =300a(4) =1960a(5) =11340a(6) =60984a(7) =312312a(8) =1544400a(9) =7438860a(10) =35103640a(11) =162954792a(12) =746347056a(13) =3380195000a(14) =15164074800a(15) =67476121200a(16) =298135873440
External references
- oeis: A273325