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A376960
a(n) = least k such that (3n Pi/4)^(2k+1)/(2k+1)! < 1.
10
1, 2, 5, 8, 11, 15, 18, 21, 24, 27, 30, 34, 37, 40, 43, 46, 50, 53, 56, 59, 62, 66, 69, 72, 75, 78, 82, 85, 88, 91, 94, 97, 101, 104, 107, 110, 113, 117, 120, 123, 126, 129, 133, 136, 139, 142, 145, 149, 152, 155, 158, 161, 165, 168, 171, 174, 177, 181, 184
OFFSET
0,2
COMMENTS
The numbers (3n Pi/4)^(2k+1)/(2k+1)! are the coefficients in the Maclaurin series for sin x when x = 3Pi/4. If m>a(n), then (n 3Pi/4)^(2k+1)/(2k+1)! < 1.
MATHEMATICA
a[n_] := Select[Range[z], (3n Pi/4)^(2 # + 1)/(2 # + 1)! < 1 &, 1]
Flatten[Table[a[n], {n, 0, 100}]]
KEYWORD
nonn
AUTHOR
Clark Kimberling, Oct 17 2024
STATUS
approved