A262297 - OEIS

%I #11 Jan 05 2016 11:29:40

%S 1,6,17,44,97,208,429,884,1814

%N Length of longest chain of nonempty proper inverse subsemigroups of the monoid of partial injective orientation-preserving functions of a chain with n elements.

%H P. J. Cameron, M. Gadouleau, J. D. Mitchell, Y. Peresse, <a href="http://arxiv.org/abs/1501.06394">Chains of subsemigroups</a>, arXiv preprint arXiv:1501.06394 [math.GR], 2015.

%K nonn,more

%O 1,2

%A _N. J. A. Sloane_, Sep 21 2015