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A194684 Number of k in [1,n] for which <r^n>+<r^k> > 1, where < > = fractional part, and r=(1+sqrt(3))/2. 4
0, 2, 2, 2, 5, 3, 7, 1, 7, 8, 11, 3, 11, 12, 12, 0, 15, 6, 16, 19, 7, 5, 21, 12, 23, 0, 15, 15, 7, 15, 21, 10, 23, 8, 0, 24, 26, 19, 10, 0, 28, 29, 21, 39, 0, 43, 47, 24, 46, 39, 11, 3, 37, 40, 3, 49, 26, 51, 41, 3, 52, 23, 16, 57, 4, 3, 43, 45, 27, 13, 26, 68, 50, 49, 37
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OFFSET
1,2
LINKS
MATHEMATICA
r = 1/2 + Sqrt[3]/2; z = 15;
p[x_]:= FractionalPart[x]; f[x_]:= Floor[x];
w[n_, k_]:= p[r^n] + p[r^k] - p[r^n + r^k]
Flatten[Table[w[n, k], {n, 1, z}, {k, 1, n}]]
TableForm[Table[w[n, k], {n, 1, z}, {k, 1, n}]]
s[n_]:= Sum[w[n, k], {k, 1, n}]
Table[s[n], {n, 1, 100}] (*A194684*)
h[n_, k_]:= f[p[n*r] + p[k*r]]
Flatten[Table[h[n, k], {n, 1, z}, {k, 1, n}]]
TableForm[Table[h[n, k], {n, 1, z}, {k, 1, n}]]
t[n_]:= Sum[h[n, k], {k, 1, n}]
Table[t[n], {n, 1, 100}] (*A194686*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling,Sep 01 2011
STATUS
approved

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Last modified September 19 10:42 EDT 2024. Contains 376008 sequences. (Running on oeis4.)