This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A276838 Number of permutations of [n] such that for each cycle c the smallest integer interval containing all elements of c has at most four elements. 3
 1, 1, 2, 6, 24, 60, 150, 399, 1145, 3132, 8420, 22716, 62128, 169536, 460885, 1251777, 3406238, 9272354, 25229036, 68622196, 186682470, 507925571, 1381929921, 3759616968, 10228269080, 27827267544, 75707898304, 205971928848, 560368255081, 1524544463441 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Alois P. Heinz, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (1,2,2,12,8,-2,-5,-1). FORMULA G.f.: -(x-1)*(x+1)/(x^8+5*x^7+2*x^6-8*x^5-12*x^4-2*x^3-2*x^2-x+1). MATHEMATICA CoefficientList[Series[-(x - 1) (x + 1)/(x^8 + 5 x^7 + 2 x^6 - 8 x^5 - 12 x^4 - 2 x^3 - 2 x^2 - x + 1), {x, 0, 29}], x] (* Michael De Vlieger, Oct 14 2017 *) CROSSREFS Column k=4 of A276837. Cf. A276720. Sequence in context: A289161 A118038 A240428 * A022917 A189855 A189566 Adjacent sequences:  A276835 A276836 A276837 * A276839 A276840 A276841 KEYWORD nonn,easy AUTHOR Alois P. Heinz, Sep 20 2016 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified November 14 03:52 EST 2018. Contains 317159 sequences. (Running on oeis4.)