Sum of the number of arcs describing the set partitions of {1,2,...,n}.
A200660
Sum of the number of arcs describing the set partitions of {1,2,...,n}.
Terms
- a(0) =0a(1) =1a(2) =8a(3) =49a(4) =284a(5) =1658a(6) =9974a(7) =62375a(8) =406832a(9) =2769493a(10) =19668054a(11) =145559632a(12) =1121153604a(13) =8974604065a(14) =74553168520a(15) =641808575961
External references
- oeis: A200660