OFFSET
0,3
LINKS
M. Albert, R. Aldred, M. Atkinson, C Handley, D. Holton, D. McCaughan and H. van Ditmarsch, Sorting Classes, Elec. J. of Comb., Vol. 12 (2005), R31.
Index entries for linear recurrences with constant coefficients, signature (4,-2,4,0,-1).
FORMULA
a(n) = 4*a(n-1)-2*a(n-2)+4*a(n-3)-a(n-5).
G.f.: 1+x*(1-2*x-2*x^3+29*x^4)/(1-4*x+2*x^2-4*x^3+x^5). - Colin Barker, Jan 16 2012
MATHEMATICA
a[1] = 1; a[2] = 2; a[3] = 6; a[4] = 22; a[5] = 113; a[n_] := a[n] = 4a[n - 1] - 2a[n - 2] + 4a[n - 3] - a[n - 5]; Table[ a[n], {n, 25}] (* Robert G. Wilson v, Nov 04 2005 *)
LinearRecurrence[{4, -2, 4, 0, -1}, {1, 2, 6, 22, 113}, 30] (* Harvey P. Dale, Jun 03 2019 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Len Smiley, Nov 01 2005
EXTENSIONS
More terms from Robert G. Wilson v, Nov 04 2005
a(0)=1 prepended by Alois P. Heinz, Mar 12 2024
STATUS
approved