Number of set partitions of [n] such that for each pair of consecutive blocks (b,b+1) exactly one pair of consecutive numbers (i,i+1) exists with i member of b and i+1 member of b+1.
A272064
Number of set partitions of [n] such that for each pair of consecutive blocks (b,b+1) exactly one pair of consecutive numbers (i,i+1) exists with i member of b and i+1 member of b+1.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =13a(5) =35a(6) =102a(7) =332a(8) =1205a(9) =4796a(10) =20640a(11) =95197a(12) =467694a(13) =2435804a(14) =13394117a(15) =77490260a(16) =470198899a(17) =2984034004a(18) =19757370537a(19) =136171758636a(20) =975002124101
External references
- oeis: A272064