0,2
Is this the same as A027974? - R. J. Mathar, Oct 23 2008
Table of n, a(n) for n=0..28.
Philipp Emanuel Weidmann, The Sequencer OEIS Survey
Susanne Wienand, Suggestion for a proof of Philipp Emanuel Weidman's conjecture concerning A027983
Conjectured formula: a(n) = 2 * a(n - 1) + L(n + 1), where L(m) is the m-th Lucas number, as in A000032. - David A. Corneth, Apr 16 2015
Conjectures from Colin Barker, Feb 17 2016: (Start)
a(n) = 2^(-1-n)*(4^(2+n)+(1-sqrt(5))^n*(-7+3*sqrt(5))-(1+sqrt(5))^n*(7+3*sqrt(5))).
a(n) = 3*a(n-1)-a(n-2)-2*a(n-3) for n>2.
G.f.: (1+2*x) / ((1-2*x)*(1-x-x^2)).
(End)
Sequence in context: A066767 A227200 A027974 * A142585 A234097 A211562
Adjacent sequences: A027980 A027981 A027982 * A027984 A027985 A027986
nonn
Clark Kimberling
approved