Search: id:A037026 Results 1-1 of 1 results found. %I A037026 %S A037026 0,1,1,1,2,2,4,5,9,15,28,45,73,116,199,345,601,1021,1738,2987,5244, %T A037026 9321,16720,30103,54345,97996,176011,314045,556577,980852,1722451, %U A037026 3020214,5298570,9316456,16440262,29136489,51860214,92643425,165934156 %N A037026 B-trees of order 4 with n leaves. %H A037026 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %H A037026 Index entries for sequences related to rooted trees %p A037026 spec := [ B, {B=Union(Z, Subst(M, B)), M=Union(Prod(Z,Z),Prod(Z,Z,Z), Prod(Z$4))} ]: [ seq(combstruct[count](spec, size=n), n=0..42) ]; %Y A037026 Cf. A014535. %Y A037026 Sequence in context: A050192 A007147 A127968 this_sequence A116651 A135586 A116646 %Y A037026 Adjacent sequences: A037023 A037024 A037025 this_sequence A037027 A037028 A037029 %K A037026 nonn %O A037026 0,5 %A A037026 N. J. A. Sloane (njas(AT)research.att.com), Paul.Zimmermann(AT)loria.fr Search completed in 0.001 seconds