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 A303983 Decimal expansion of 2*sin((37/384)*Pi). 1
 5, 9, 6, 2, 0, 7, 6, 5, 0, 0, 8, 5, 4, 7, 9, 6, 8, 5, 0, 6, 9, 2, 1, 9, 4, 5, 1, 3, 5, 2, 0, 1, 3, 8, 2, 1, 7, 2, 6, 7, 6, 7, 5, 9, 9, 0, 2, 0, 0, 6, 7, 7, 0, 3, 3, 3, 1, 7, 8, 7, 9, 2, 1, 6, 4, 6, 0, 8, 4, 3, 4, 0, 4, 4, 6, 3, 0, 1, 1, 9, 7, 2, 4, 4, 4, 4, 3, 0, 2, 1, 6, 4, 3, 7, 1, 6, 2, 6, 0, 4, 1, 3, 4, 9, 6, 5 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS This constant is a solution x of R(45, x) = sqrt(2 + sqrt(2 - sqrt(2 - sqrt(2 - sqrt(2 - sqrt(2)))))) = A303982, with the monic Chebyshev polynomial of the first kind, called R, with coefficients given in A127672. This polynomial with the given value appears in the historic problem (exemplum secundum) posed by Adriaan van Roomen (Adrianus Romanus) in his Ideae mathematicae from 1593. However, the two solutions given there (in two different printings) are incorrect. See A303982 for comments and the Vieta link. LINKS Adriano Romano Lovaniensi, Ideae Mathematicae, 1593. Adriano Romano Lovaniensi, Ideae Mathematicae, 1593 [alternative link with other exemplum 2]. FORMULA 2*sin((37/384)*Pi) = sqrt(2 - sqrt(2 + sqrt(2 - sqrt(2 + sqrt(2 - sqrt(2 + sqrt(3))))))). EXAMPLE 0.59620765008547968506921945135201382172676759902006770333178792164608434044... MAPLE a:=evalf(2*sin((37/384)*Pi), 160): b:=[]: for n from 1 to 106 do b:=[op(b), trunc(10*a)]: a:=evalf(frac(10*a), 109): od: print(op(b)); # Paolo P. Lava, May 07 2018 PROG (PARI) 2*sin(37*Pi/384) \\ Altug Alkan, May 06 2018 CROSSREFS Cf. A127672, A303982. Sequence in context: A134879 A051158 A117605 * A073003 A087498 A274633 Adjacent sequences:  A303980 A303981 A303982 * A303984 A303985 A303986 KEYWORD nonn,cons,easy AUTHOR Wolfdieter Lang, May 04 2018 STATUS approved

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Last modified April 17 02:26 EDT 2021. Contains 343059 sequences. (Running on oeis4.)