Number of up-down sequences of length n and values in {1,2,...,n}.

A276312

Number of up-down sequences of length n and values in {1,2,...,n}.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =5a(4) =31a(5) =246a(6) =2353a(7) =26585a(8) =345775a(9) =5094220a(10) =83833256a(11) =1524414737a(12) =30353430420a(13) =656851828075

External references