The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A122583 a(n) = a(n - 1) - 2*a(n - 2) + a(n - 3) + 3*(-2*a(n - 4) + a(n - 5)). 1
 1, 1, 1, 1, 1, -3, -7, -3, 5, 25, 45, -3, -107, -191, -175, 253, 1045, 1189, -171, -3547, -7527, -4603, 11497, 33945, 40869, -10487, -141071, -248407, -120131, 421141, 1227961, 1332777, -726439, -5051271, -8369959, -3306635, 16738977, 43110597, 41391949, -33360335, -183387403, -283721435 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS This recursion is inspired by Ulam's early experiments in derivative recursions. LINKS Index entries for linear recurrences with constant coefficients, signature (1,-2,1,-6,3). FORMULA G.f.:(-1-7*x^4-x^3-2*x^2)*x/(-1+3*x^5-6*x^4+x^3-2*x^2+x). - Maksym Voznyy (voznyy(AT)mail.ru), Aug 11 2009 MAPLE A122583 := proc(n) option remember ; if n <= 5 then 1; else A122583(n-1)-2*A122583(n-2)+A122583(n-3)+3*(-2*A122583(n-4)+A122583(n-5)) ; fi ; end: seq(A122583(n), n=1..80) ; # R. J. Mathar, Sep 18 2007 MATHEMATICA a[0] = 1; a[1] = 1; a[2] = 1; a[3] = 1; a[4] = 1; a[n_] := a[n] = a[n - 1] - 2*a[n - 2] + a[n - 3] + 3*(-2*a[n - 4] + a[n - 5]); Table[a[n], {n, 0, 30}] CROSSREFS Sequence in context: A193534 A096247 A337013 * A001265 A060443 A020810 Adjacent sequences:  A122580 A122581 A122582 * A122584 A122585 A122586 KEYWORD sign AUTHOR Roger L. Bagula, Sep 19 2006 EXTENSIONS Edited by N. J. A. Sloane, Oct 01 2006 More terms from R. J. Mathar, Sep 18 2007 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 July 25 00:32 EDT 2021. Contains 346273 sequences. (Running on oeis4.)