Number of set partitions of [n] having exactly three pairs (m,m+1) such that m+1 is in some block b and m is in block b+1.
A270957
Number of set partitions of [n] having exactly three pairs (m,m+1) such that m+1 is in some block b and m is in block b+1.
Terms
- a(0) =1a(1) =21a(2) =197a(3) =1421a(4) =9573a(5) =64724a(6) =449567a(7) =3230230a(8) =24053169a(9) =185658621a(10) =1484943532a(11) =12299106220a(12) =105400873263a(13) =933717036862
External references
- oeis: A270957