Number of involutions of length 2n which are invariant under the reverse-complement map and have no decreasing subsequence of length 7.

A145867

Number of involutions of length 2n which are invariant under the reverse-complement map and have no decreasing subsequence of length 7.

Terms

    a(0) =1a(1) =2a(2) =6a(3) =20a(4) =74a(5) =292a(6) =1214a(7) =5252a(8) =23468a(9) =107672a(10) =505048a(11) =2413776a(12) =11723188a(13) =57737032a(14) =287853518a(15) =1450697572a(16) =7381645844a(17) =37884748712a(18) =195947389208

External references