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A283745
a(n) = least m such that 1/(n+1) < f(m) < 1/n, where f(m) = fractional part of m*(golden ratio).
3
1, 4, 7, 2, 10, 31, 52, 18, 39, 94, 5, 60, 115, 26, 170, 81, 225, 369, 136, 280, 47, 191, 568, 335, 102, 479, 246, 623, 13, 390, 157, 1144, 534, 911, 301, 678, 1665, 68, 445, 1432, 822, 1809, 212, 2186, 589, 1576, 2563, 966, 356, 1343, 3927, 733, 3317, 1720
OFFSET
1,2
COMMENTS
This is column 1 of A283738; |a(n+1)-a(n)| is a Fibonacci number for n>=1.
MATHEMATICA
g = GoldenRatio; z = 10000; t = Table[N[FractionalPart[n*g]], {n, 1, z}];
r[k_] := Select[Range[z], 1/(k + 1) < t[[#]] < 1/k &, 1];
Flatten[Table[r[k], {k, 1, 200}]] (* A283745 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Mar 17 2017
STATUS
approved