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A197724
Decimal expansion of Pi^2/(2 + Pi).
2
1, 9, 1, 9, 5, 6, 1, 7, 1, 2, 8, 8, 6, 4, 7, 8, 6, 5, 9, 7, 0, 1, 4, 5, 2, 6, 0, 7, 3, 7, 1, 5, 6, 5, 1, 6, 0, 7, 2, 2, 3, 2, 4, 1, 3, 3, 4, 6, 2, 9, 2, 0, 2, 3, 0, 5, 5, 7, 1, 1, 1, 0, 4, 2, 2, 2, 2, 8, 8, 6, 7, 3, 8, 4, 1, 3, 5, 7, 7, 3, 2, 1, 3, 1, 3, 2, 9, 2, 0, 5, 8, 4, 2, 8, 7, 6, 8, 4, 5
OFFSET
1,2
COMMENTS
Least x > 0 such that sin(b*x) = cos(c*x) (and also sin(c*x) = cos(b*x)), where b=1/2 and c=1/Pi; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.
EXAMPLE
1.91956171288647865970145260737156516072232...
MATHEMATICA
b = 1/2; c = 1/Pi;
t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, 1.9, 1.92}]
N[Pi/(2*b + 2*c), 110]
RealDigits[%] (* A197724 *)
Simplify[Pi/(2*b + 2*c)]
Plot[{Sin[b*x], Cos[c*x]}, {x, 0, 2.8}]
RealDigits[Pi^2/(2+Pi), 10, 120][[1]] (* Harvey P. Dale, Mar 19 2023 *)
CROSSREFS
Cf. A197682.
Sequence in context: A021525 A371935 A297013 * A176518 A154697 A187368
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 17 2011
STATUS
approved