%I #6 Jan 31 2016 12:11:33
%S 1,1,5,16,55,235,1102,5757,33251
%N Number of types of lambda-terms of term size n.
%H P. Tarau, <a href="http://arxiv.org/abs/1507.06944">A Logic Programming Playground for Lambda Terms, Combinators, Types and Tree-based Arithmetic Computations</a>, arXiv preprint arXiv:1507.06944 [cs.LO], 2015.
%Y Cf. A220471.
%K nonn,more
%O 1,3
%A _N. J. A. Sloane_, Jan 30 2016