Search: id:A054873 Results 1-1 of 1 results found. %I A054873 %S A054873 1,2,6,24,120,720,5040,40320,357840,3427200,34685280,365541120, %T A054873 3971615760,44181889920,500788985760,5763231048960,67163932069920, %U A054873 791030794095360,9400660122813120,112587818898562560 %N A054873 Number of (S_5 67)-avoiding permutations. %D A054873 E. Barcucci, A. Del Lungo, E. Pergola, R. Pinzani, Permutations avoiding an increasing number of length-increasing forbidden subsequences, Discrete MAthematics and Theoretical Computer Science 4, 2000, 31-44 %H A054873 E. Barcucci, A. Del Lungo, E. Pergola and R. Pinzani, Permutations avoiding an increasing number of length-increasing forbidden subsequences %F A054873 f := (x, j)->1-(j+1)*x- sqrt(1-2*(j+1)*x+(j-1)^2*x^2); t := (x, j)->sum(k!*x^k, k=1..(j-1)); s := (x, j)->x^(j-2)*(j-1)!*(f(x, j))/(2)+ t(x, j); j := 6 %Y A054873 Cf. A000108. %Y A054873 Sequence in context: A152644 A152637 A152645 this_sequence A072132 A066459 A071937 %Y A054873 Adjacent sequences: A054870 A054871 A054872 this_sequence A054874 A054875 A054876 %K A054873 nonn %O A054873 1,2 %A A054873 Elisa Pergola (elisa(AT)dsi.unifi.it), May 26 2000 Search completed in 0.001 seconds