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A197685
Decimal expansion of Pi^2/(4 + 2*Pi).
2
9, 5, 9, 7, 8, 0, 8, 5, 6, 4, 4, 3, 2, 3, 9, 3, 2, 9, 8, 5, 0, 7, 2, 6, 3, 0, 3, 6, 8, 5, 7, 8, 2, 5, 8, 0, 3, 6, 1, 1, 6, 2, 0, 6, 6, 7, 3, 1, 4, 6, 0, 1, 1, 5, 2, 7, 8, 5, 5, 5, 5, 2, 1, 1, 1, 1, 4, 4, 3, 3, 6, 9, 2, 0, 6, 7, 8, 8, 6, 6, 0, 6, 5, 6, 6, 4, 6, 0, 2, 9, 2, 1, 4, 3, 8, 4, 2, 2, 8
OFFSET
0,1
COMMENTS
Least x > 0 such that sin(bx) = cos(cx) (and also sin(cx) = cos(bx)), where b=1 and c=2/Pi; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.
EXAMPLE
x=0.9597808564432393298507263036857825803611620667...
MATHEMATICA
b = 1; c = 2/Pi;
t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, .9, 1}]
N[Pi/(2*b + 2*c), 110]
RealDigits[%] (* A197685 *)
Simplify[Pi/(2*b + 2*c)]
Plot[{Sin[b*x], Cos[c*x]}, {x, 0, Pi/2}]
CROSSREFS
Cf. A197682.
Sequence in context: A341438 A265290 A293079 * A378864 A220510 A078086
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 17 2011
STATUS
approved