A196612 - OEIS

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A196612

Decimal expansion of the least x>0 satisfying 2*sec(x)=x.

5, 1, 1, 4, 1, 8, 2, 1, 8, 7, 8, 5, 5, 8, 1, 5, 8, 7, 4, 9, 1, 9, 7, 7, 5, 5, 4, 8, 9, 2, 6, 8, 0, 0, 7, 7, 3, 5, 0, 5, 6, 3, 6, 1, 9, 9, 8, 1, 4, 4, 3, 8, 7, 6, 0, 0, 4, 6, 6, 2, 1, 8, 7, 5, 9, 2, 6, 8, 6, 5, 7, 6, 6, 0, 3, 4, 2, 7, 2, 0, 0, 9, 7, 7, 5, 6, 4, 3, 8, 5, 9, 1, 9, 9, 5, 0, 9, 7, 9, 6, 7

(list; constant; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..101.

EXAMPLE

x=5.11418218785581587491977554892680077350563...

MATHEMATICA

Plot[{1/x, 2/x, 3/x, 4/x, Cos[x]}, {x, 0, 2 Pi}]

t = x /. FindRoot[1/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]

RealDigits[t] (* A133868 *)

t = x /. FindRoot[2/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]