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 A324843 #6 Mar 19 2019 07:15:01 %S A324843 1,1,1,2,2,4,4,8,9,15,17,31,35,57,70,111,136,213,265,405,517,763,987, %T A324843 1458,1893,2736,3611,5161,6836,9702 %N A324843 Number of unlabeled rooted trees with n nodes where the branches of any branch of any terminal subtree form a submultiset of the branches of the same subtree. %C A324843 A subset of totally transitive rooted trees (A318185). %e A324843 The a(1) = 1 through a(8) = 8 rooted trees: %e A324843 o (o) (oo) (ooo) (oooo) (ooooo) (oooooo) (ooooooo) %e A324843 (o(o)) (oo(o)) (oo(oo)) (ooo(oo)) (ooo(ooo)) %e A324843 (ooo(o)) (oooo(o)) (oooo(oo)) %e A324843 (o(o)(o)) (oo(o)(o)) (ooooo(o)) %e A324843 (oo(o)(oo)) %e A324843 (ooo(o)(o)) %e A324843 (o(o)(o)(o)) %e A324843 (o(o)(o(o))) %t A324843 submultQ[cap_,fat_]:=And@@Function[i,Count[fat,i]>=Count[cap,i]]/@Union[List@@cap]; %t A324843 rallt[n_]:=Select[Union[Sort/@Join@@(Tuples[rallt/@#]&/@IntegerPartitions[n-1])],And@@Table[submultQ[b,#],{b,#}]&]; %t A324843 Table[Length[rallt[n]],{n,10}] %Y A324843 The Matula-Goebel numbers of these trees are given by A324842. %Y A324843 Cf. A000081, A279861, A290689, A290822, A318185. %Y A324843 Cf. A324704, A324736, A324748, A324753, A324847, A324848, A324854. %K A324843 nonn,more %O A324843 1,4 %A A324843 _Gus Wiseman_, Mar 18 2019