This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A324844 #5 Mar 19 2019 07:15:13 %S A324844 1,1,2,3,7,13,32,71,170,406,1002,2469,6204,15644,39871,102116,263325, %T A324844 682079,1775600,4640220 %N A324844 Number of unlabeled rooted trees with n nodes where the branches of no non-leaf branch of any terminal subtree form a submultiset of the branches of the same subtree. %e A324844 The a(1) = 1 through a(6) = 13 rooted trees: %e A324844 o (o) (oo) (ooo) (oooo) (ooooo) %e A324844 ((o)) ((oo)) ((ooo)) ((oooo)) %e A324844 (((o))) (o(oo)) (o(ooo)) %e A324844 (((oo))) (((ooo))) %e A324844 ((o)(o)) ((o)(oo)) %e A324844 (o((o))) ((o(oo))) %e A324844 ((((o)))) (o((oo))) %e A324844 (oo((o))) %e A324844 ((((oo)))) %e A324844 (((o)(o))) %e A324844 ((o((o)))) %e A324844 (o(((o)))) %e A324844 (((((o))))) %t A324844 submultQ[cap_,fat_]:=And@@Function[i,Count[fat,i]>=Count[cap,i]]/@Union[List@@cap]; %t A324844 rallt[n_]:=Select[Union[Sort/@Join@@(Tuples[rallt/@#]&/@IntegerPartitions[n-1])],And@@Table[!submultQ[b,#],{b,DeleteCases[#,{}]}]&]; %t A324844 Table[Length[rallt[n]],{n,10}] %Y A324844 The Matula-Goebel numbers of these trees are given by A324845. %Y A324844 Cf. A000081, A290689, A306844, A318185. %Y A324844 Cf. A324694, A324738, A324744, A324749, A324754, A324759, A324765, A324768, A324838, A324843, A324846, A324847, A324848, A324849. %K A324844 nonn %O A324844 1,3 %A A324844 _Gus Wiseman_, Mar 18 2019