Number of set partitions of [n] such that for each pair of blocks (b,c) with b<c at least one pair of consecutive numbers (i,i+1) exists with i member of b and i+1 member of c.
A272105
Number of set partitions of [n] such that for each pair of blocks (b,c) with b<c at least one pair of consecutive numbers (i,i+1) exists with i member of b and i+1 member of c.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =17a(6) =41a(7) =115a(8) =362a(9) =1208a(10) =4112a(11) =14107a(12) =49187a(13) =178049
External references
- oeis: A272105