Number of ordered set partitions of [n] with nondecreasing block sizes and maximal block size equal to two.
A272492
Number of ordered set partitions of [n] with nondecreasing block sizes and maximal block size equal to two.
Terms
- a(0) =1a(1) =3a(2) =18a(3) =90a(4) =630a(5) =4410a(6) =37800a(7) =340200a(8) =3515400a(9) =38669400a(10) =471517200a(11) =6129723600a(12) =86497210800
External references
- oeis: A272492