Search: id:A033312 Results 1-1 of 1 results found. %I A033312 %S A033312 0,0,1,5,23,119,719,5039,40319,362879,3628799,39916799,479001599, %T A033312 6227020799,87178291199,1307674367999,20922789887999,355687428095999, %U A033312 6402373705727999,121645100408831999,2432902008176639999 %N A033312 n! - 1. %C A033312 a(n) gives the index number in any table of permutations of the entry in which the last n+1 items are reversed. - Eugene McDonnell (eemcd(AT)mac.com), Dec 03 2004 %C A033312 a(n), n>=1, has the factorial representation [n-1,n-2,...,1,0]. The (unique) factorial representation of a number m from {0,1,...n!-1} is m =sum(m_j(n)*j!, j=0..n-1) with m_j(n) from {0,1,..,j}, n>=1. This is encoded as [m_{n-1}, m_{n-2},...,m+1,m_0] with m_0=0. This can be interpreted as (D. N.) Lehmer code for the lexicographic rank of permutations of the symmetric group S_n (see the W. Lang link under A136663). The Lehmer code [n-1, n-2,...,1,0] stands for the permutation [n,n-1,...,1] (the last in lexicographic order). - Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), May 21 2008 %D A033312 Problem 598, J. Rec. Math., 11 (1978), 68-69. %D A033312 A. T. Benjamin and J. J. Quinn, Proofs that really count: the art of combinatorial proof, M.A.A. 2003, id. 181. %H A033312 Hisanori Mishima, Factorizations of many number sequences %H A033312 Hisanori Mishima, Factorizations of many number sequences %H A033312 Andrew Walker, Factors of n! +- 1 %H A033312 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %H A033312 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %H A033312 R. G. Wilson v, Explicit factorizations %H A033312 Index entries for sequences related to factorial numbers %H A033312 G. P. Michon, Wilson's Theorem %F A033312 Equals Sum_{k=1..n} k*k!. %F A033312 a(n) = a(n-1)*(n-1) + a(n-1) + n-1, a(0)=0. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 03 2003 %t A033312 f[n_]:=n!-1;lst={};Do[AppendTo[lst,f[n]],{n,0,5!}];lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jun 27 2009] %Y A033312 Cf. A000142, A038507. %Y A033312 Cf. A002582; A054415; A056110; A002982. %Y A033312 Sequence in context: A167248 A005393 A162815 this_sequence A151881 A121636 A020032 %Y A033312 Adjacent sequences: A033309 A033310 A033311 this_sequence A033313 A033314 A033315 %K A033312 nonn %O A033312 0,4 %A A033312 Eric Weisstein (eric(AT)weisstein.com) Search completed in 0.002 seconds