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 A170942 Take the permutations of lengths 1, 2, 3, ... arranged lexicographically, and replace each permutation with the number of its fixed points. 19
 1, 2, 0, 3, 1, 1, 0, 0, 1, 4, 2, 2, 1, 1, 2, 2, 0, 1, 0, 0, 1, 1, 0, 2, 1, 0, 0, 0, 1, 1, 2, 0, 0, 5, 3, 3, 2, 2, 3, 3, 1, 2, 1, 1, 2, 2, 1, 3, 2, 1, 1, 1, 2, 2, 3, 1, 1, 3, 1, 1, 0, 0, 1, 2, 0, 1, 0, 0, 1, 1, 0, 2, 1, 0, 0, 0, 1, 1, 2, 0, 0, 2, 0, 1, 0, 0, 1, 3, 1, 2, 1, 1, 2, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Length of n-th row = sum of n-th row = n!; number of zeros in n-th row = A000166(n); number of positive terms in n-th row = A002467(n). [Reinhard Zumkeller, Mar 29 2012] LINKS Reinhard Zumkeller, Rows n=1..7 of triangle, flattened FindStat - Combinatorial Statistic Finder, The number of fixed points of a permutation EXAMPLE 123,132,213,231,312,321 (corresponding to 3rd row of triangle A030298) have respectively 3,1,1,0,0,1 fixed points. PROG (Haskell) import Data.List (permutations, sort) a170942 n k = a170942_tabf !! (n-1) (k-1) a170942_row n = map fps \$ sort \$ permutations [1..n] where    fps perm = sum \$ map fromEnum \$ zipWith (==) perm [1..n] a170942_tabf = map a170942_row [1..] -- Reinhard Zumkeller, Mar 29 2012 CROSSREFS Cf. A030298, A030299. Cf. A008290, A000166, A000240, A000387, A000449, A000475, A129135, A129136, A129149, A129153, A129217, A129218, A129238, A129255. Cf. A008291. Sequence in context: A299070 A209599 A238347 * A325660 A342657 A002187 Adjacent sequences:  A170939 A170940 A170941 * A170943 A170944 A170945 KEYWORD nonn,tabf AUTHOR Neven Juric (neven.juric(AT)apis-it.hr) and N. J. A. Sloane, Feb 23 2010 EXTENSIONS a(36)-a(105) from John W. Layman, Feb 23 2010 Keyword tabf added by Reinhard Zumkeller, Mar 29 2012 STATUS approved

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Last modified April 13 22:53 EDT 2021. Contains 342941 sequences. (Running on oeis4.)