A270962 Number of set partitions of [n] having exactly eight pairs (m,m+1) such that m+1 is in some block b and m is in block b+1.

15, 857, 21129, 361154, 5138182, 66407157, 816411988, 9796844472, 116493895521, 1385342513224, 16571907424860, 200166968890873, 2447436683633895, 30343738969483443, 381914993014556712, 4883614045607479339, 63476602847240143719, 838919983940694715522

Offset

13,1

Links

Alois P. Heinz, Table of n, a(n) for n = 13..220

Wikipedia, Partition of a set

Example

a(13) = 15: 1369(13)|258(12)|47(11)|(10), 136(10)(13)|259(12)|48(11)|7, 136(10)|259(13)|48(12)|7(11), 136(10)|259|48(13)|7(12)|(11), 136(13)|259(12)|48(11)|7(10), 136|259(13)|48(12)|7(11)|(10), 136(13)|25(12)|48(11)|7(10)|9, 139(13)|258(12)|47(11)|6(10), 139|258(13)|47(12)|6(11)|(10), 13(13)|258(12)|47(11)|6(10)|9, 138(13)|27(12)|46(11)|5(10)|9, 159(13)|248(12)|37(11)|6(10), 159|248(13)|37(12)|6(11)|(10), 15(13)|248(12)|37(11)|6(10)|9, 18(13)|247(12)|36(11)|5(10)|9.

Crossrefs

Column k=8 of A270953.

Sequence in context: A281695 A223276 A233019 * A223818 A208349 A358802

Adjacent sequences: A270959 A270960 A270961 * A270963 A270964 A270965

Keyword

nonn

Author

Alois P. Heinz, Mar 26 2016

Status

approved