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A332499
Least positive integer k such that tan(n*k)*tan(n*k + k) < 0.
2
1, 1, 11, 1, 1, 5, 2, 1, 3, 2, 1, 2, 3, 1, 2, 5, 1, 1, 10, 1, 1, 177, 1, 1, 11, 1, 1, 5, 2, 1, 3, 2, 1, 2, 3, 1, 2, 5, 1, 1, 9, 1, 1, 88, 1, 1, 12, 1, 1, 5, 2, 1, 3, 2, 1, 2, 3, 1, 2, 5, 1, 1, 9, 1, 1, 59, 1, 1, 13, 1, 1, 6, 2, 1, 3, 2, 1, 2, 3, 1, 2, 4, 1
OFFSET
1,3
COMMENTS
a(n) = least positive integer k such that tan(n*k) and tan(n*k + k) have opposite signs.
EXAMPLE
The signs of tan(6), tan(12), ..., tan(36) are indicated by - - - - - +; that's five -'s followed by +, so that a(6) = 5.
MATHEMATICA
Table[First[Map[Length, Split[Table[Sign[Tan[k n]], {k, 1, 500}]]]], {n, 1, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 21 2020
STATUS
approved