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A197725 Decimal expansion of Pi^2/(4 + Pi). 2
1, 3, 8, 1, 9, 8, 9, 2, 6, 7, 6, 3, 6, 0, 2, 2, 7, 4, 2, 1, 0, 4, 5, 5, 7, 8, 8, 5, 2, 2, 4, 6, 4, 9, 3, 4, 9, 0, 0, 0, 4, 1, 9, 6, 2, 6, 4, 2, 4, 3, 4, 8, 8, 5, 5, 9, 1, 1, 1, 4, 5, 1, 1, 9, 8, 0, 4, 4, 5, 5, 5, 5, 3, 9, 5, 0, 5, 9, 6, 6, 0, 7, 8, 8, 0, 6, 3, 2, 9, 9, 3, 5, 9, 4, 4, 1, 1, 7, 2 (list; constant; graph; refs; listen; history; text; internal format)
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=2/Pi; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.

LINKS

Table of n, a(n) for n=1..99.

EXAMPLE

x=1.38198926763602274210455788522464934900041...

MATHEMATICA

b = 1/2; c = 2/Pi;

t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, 1.37, 1.39}]

N[Pi/(2*b + 2*c), 110]

RealDigits[%]  (* A197725 *)

Simplify[Pi/(2*b + 2*c)]

Plot[{Sin[b*x], Cos[c*x]}, {x, 0, 2.8}]

RealDigits[Pi^2/(4+Pi), 10, 120][[1]] (* Harvey P. Dale, Jul 01 2013 *)

CROSSREFS

Cf. A197682.

Sequence in context: A094874 A132338 A132702 * A288875 A152230 A181371

Adjacent sequences:  A197722 A197723 A197724 * A197726 A197727 A197728

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 17 2011

STATUS

approved

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Last modified December 3 02:46 EST 2021. Contains 349445 sequences. (Running on oeis4.)