Search: id:A006541 Results 1-1 of 1 results found. %I A006541 M4920 %S A006541 1,1,13,4683,102247563,230283190977853,81124824998504073881821, %T A006541 6297562064950066033518373935334635, %U A006541 144199280951655469628360978109406917583513090155 %N A006541 Number of dissimilarity relations on an n-set. %D A006541 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A006541 M. Schader, Hierarchical analysis: classification with ordinal object dissimilarities, Metrika, 27 (1980), 127-132. %F A006541 Sum_{i=0..m-1} (m-i)!*Stirling2(m, m-i), where m = n(n-1)/2. %Y A006541 Cf. A005121. %Y A006541 A000670(n(n-1)/2). %Y A006541 Sequence in context: A094316 A057842 A023345 this_sequence A103857 A032463 A060887 %Y A006541 Adjacent sequences: A006538 A006539 A006540 this_sequence A006542 A006543 A006544 %K A006541 nonn,nice,easy %O A006541 1,3 %A A006541 N. J. A. Sloane (njas(AT)research.att.com). %E A006541 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Jan 19 2000 Search completed in 0.001 seconds