OFFSET
1,2
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..10000
F. Miller Maley et al., Symplectic packings in cotangent bundles of tori, Experimental Mathematics, 9 (No. 3, 2000), 435-455.
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
From Colin Barker, Nov 06 2019: (Start)
G.f.: x*(1 + 2*x - 3*x^2 + 21*x^4 - 21*x^5 + 39*x^6 + 186*x^7 - 505*x^8 + 281*x^9) / (1 - x)^2.
a(n) = 2*a(n-1) - a(n-2) for n>10.
a(n) = n for n>8. (End)
EXAMPLE
1, 1/4, 1/4, 1/4, 4/25, 4/25, 9/64, 36/289, 1/9, 1/10, ...
MATHEMATICA
PadRight[{1, 4, 4, 4, 25, 25, 64, 289}, #, Range[#]] & [100] (* Paolo Xausa, Apr 02 2026 *)
CROSSREFS
KEYWORD
nonn,frac,easy,changed
AUTHOR
N. J. A. Sloane, Feb 24 2001
EXTENSIONS
Edited by N. J. A. Sloane, May 23 2014
More terms from Paolo Xausa, Apr 02 2026
STATUS
approved