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A163581
Number of zeros of sin(x) in integer intervals starting with (0,1).
1
0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0
OFFSET
0,1
FORMULA
a(n) = 1 if n < m*pi < (n+1) for any positive integer m; a(n) = 0 otherwise.
For n>0, a(A022844(n)) = 1. - Michel Marcus, Aug 07 2013
EXAMPLE
For n = 0, 1 and 2, sin(x) has no zeros in the intervals (0,1), (1,2) and (2,3), respectively, so a(0), a(1) and a(2) are all zero. For n = 3, sin(x) has a zero in the interval (3,4) at x = pi, so a(3) = 1.
CROSSREFS
Cf. A163584.
Sequence in context: A144597 A125117 A144603 * A100283 A320927 A134391
KEYWORD
nonn
AUTHOR
A. Timothy Royappa, Jul 31 2009
STATUS
approved