Number of sequences with 4 copies each of 1,2,...,n and longest increasing subsequence of length n.
A268847
Number of sequences with 4 copies each of 1,2,...,n and longest increasing subsequence of length n.
Terms
- a(0) =1a(1) =1a(2) =69a(3) =31451a(4) =46922017a(5) =162588279629
External references
- oeis: A268847