A368461 - OEIS

%I #7 Dec 26 2023 08:33:57

%S 1,1,1,2,4,8,16,33,70,151,329,723,1601,3569,8000,18015,40723,92351,

%T 209997,478598,1092856,2499567,5724970,13128115,30135636,69238343,

%U 159202607,366308948,843338278,1942591448,4476714720,10320774953,23802355725,54911686727

%N a(n) is the number of unlabeled planar modular lattices on n nodes.

%H Jukka Kohonen, <a href="https://bitbucket.org/jkohonen/modular-racks/">Modular racks</a> (code to compute the numbers).

%Y Cf. A006981 (modular lattices), A343161 (planar distributive lattices).

%K nonn

%O 1,4

%A _Jukka Kohonen_, Dec 25 2023