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A197694
Decimal expansion of Pi/(4 + Pi).
2
4, 3, 9, 9, 0, 0, 8, 4, 6, 4, 8, 8, 4, 4, 2, 6, 2, 4, 0, 8, 9, 5, 2, 1, 3, 7, 4, 5, 1, 3, 7, 1, 3, 3, 8, 3, 7, 9, 9, 1, 8, 7, 4, 4, 3, 2, 3, 7, 6, 8, 9, 2, 4, 1, 2, 6, 5, 9, 4, 9, 8, 6, 8, 1, 2, 5, 8, 4, 0, 2, 1, 3, 0, 8, 3, 9, 0, 3, 0, 9, 7, 6, 8, 6, 8, 5, 0, 4, 5, 7, 9, 3, 6, 9, 2, 6, 3, 3, 5
OFFSET
0,1
COMMENTS
Least x > 0 such that sin(b*x) = cos(c*x) (and also sin(c*x) = cos(b*x)), where b=2 and c=Pi/2; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.
EXAMPLE
0.4399008464884426240895213745137133837991874432...
MATHEMATICA
b = 2; c = Pi/2;
t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, .4, .45}]
N[Pi/(2*b + 2*c), 110]
RealDigits[%] (* A197694 *)
Simplify[Pi/(2*b + 2*c)]
Plot[{Sin[b*x], Cos[c*x]}, {x, 0, 1.1}]
CROSSREFS
Cf. A197682.
Sequence in context: A370290 A275473 A131805 * A187770 A103218 A319311
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 17 2011
STATUS
approved