Search: id:A007187 Results 1-1 of 1 results found. %I A007187 M2532 %S A007187 1,3,6,9,15,20,26,34,41 %N A007187 Leech's tree-labeling problem for n nodes. %D A007187 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A007187 R. K. Guy, A quarter century of "Monthly" unsolved problems, 1969-1993, Amer Math. Monthly, 100 (1993), 945-949. %D A007187 R. K. Guy, Unsolved Problems in Number Theory, Sect. C10. %D A007187 J. Leech, On the representation of $1,2,\cdots,n$ by differences. J. London Math. Soc. 31 (1956), 160-169. %H A007187 Index entries for sequences related to trees %Y A007187 Cf. A005488. %Y A007187 Sequence in context: A049991 A143981 A031940 this_sequence A082004 A112773 A070885 %Y A007187 Adjacent sequences: A007184 A007185 A007186 this_sequence A007188 A007189 A007190 %K A007187 nonn,hard,nice %O A007187 2,2 %A A007187 N. J. A. Sloane (njas(AT)research.att.com). %E A007187 a(11)>=48, a(12)>=55. Search completed in 0.001 seconds