Number of set partitions of [n] such that all absolute differences between least elements of consecutive blocks and between consecutive elements within the blocks are not larger than three.
A287582
Number of set partitions of [n] such that all absolute differences between least elements of consecutive blocks and between consecutive elements within the blocks are not larger than three.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =15a(5) =46a(6) =139a(7) =410a(8) =1189a(9) =3397a(10) =9615a(11) =27056a(12) =75838a(13) =212088a(14) =592314a(15) =1652806a(16) =4609789a(17) =12853354a(18) =35832568a(19) =99884249a(20) =278414160a(21) =776016655a(22) =2162929636a(23) =6028494326a(24) =16802444328a(25) =46831107603a(26) =130525521011a(27) =363794294041
External references
- oeis: A287582