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A022165
First row of spectral array W(sqrt(5)-1).
9
1, 5, 6, 26, 32, 136, 168, 712, 880, 3728, 4608, 19520, 24128, 102208, 126336, 535168, 661504, 2802176, 3463680, 14672384, 18136064, 76825600, 94961664, 402264064, 497225728, 2106281984, 2603507712
OFFSET
0,2
LINKS
A. Fraenkel and C. Kimberling, Generalized Wythoff arrays, shuffles and interspersions, Discrete Mathematics 126 (1994) 137-149.
FORMULA
Conjectures: a(n) = 6*a(n-2)-4*a(n-4). G.f.: -(x+1)*(4*x^2-4*x-1) / (4*x^4-6*x^2+1). - Colin Barker, Oct 23 2014
PROG
(PARI)
\\ The first row of the generalized Wythoff array W(h),
\\ where h is an irrational number between 1 and 2.
row1(h, m) = {
my(
a=vector(m, n, floor(n*h)),
b=setminus(vector(m, n, n), a),
w=[a[1]^2, b[a[1]]],
j=3
);
while(1,
if(j%2==1,
if(w[j-1]<=#a, w=concat(w, a[w[j-1]]), return(w))
,
if(w[j-2]<=#b, w=concat(w, b[w[j-2]]), return(w))
);
j++
);
w
}
row1(sqrt(5)-1, 100000) \\ Colin Barker, Oct 23 2014
CROSSREFS
Sequence in context: A137079 A163658 A121180 * A342775 A022163 A048060
KEYWORD
nonn,more
EXTENSIONS
a(14)-a(18) from Colin Barker, Oct 23 2014 and Michel Marcus, Oct 24 2014
a(19)-a(26) from Sean A. Irvine, May 14 2019
STATUS
approved