This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A122022 a(0) = 0, a(1) = 1, a(2) = 2, a(3) = 1; for n > 3, a(n) = a(n - 1) - (n - 1)*a(n - 4). 4
 0, 1, 2, 1, 1, -3, -13, -19, -26, -2, 115, 305, 591, 615, -880, -5150, -14015, -23855, -8895, 83805, 350090, 827190, 1013985, -829725, -8881795, -28734355, -54083980, -32511130, 207297335, 1011859275, 2580294695 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA a[0] = 0; a[1] = 1; a[2] = 2; a[3] = 1; a[n_] := a[n] = a[n - 1] - (n - 1)*a[n - 4] Table[a[n], {n, 0, 30}] RecurrenceTable[{a[0]==0, a[1]==1, a[2]==2, a[3]==1, a[n]==a[n-1]- (n-1) a[n-4]}, a, {n, 30}] (* Harvey P. Dale, Nov 28 2014 *) CROSSREFS Cf. A000898, A121966, A062267. Sequence in context: A212261 A014521 A084389 * A134357 A049258 A228832 Adjacent sequences:  A122019 A122020 A122021 * A122023 A122024 A122025 KEYWORD sign AUTHOR Roger L. Bagula, Sep 12 2006 EXTENSIONS Edited by N. J. A. Sloane, Sep 12 2006 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 24 15:25 EDT 2019. Contains 323532 sequences. (Running on oeis4.)