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A086203
Decimal expansion of arctan(1/2)/Pi.
1
1, 4, 7, 5, 8, 3, 6, 1, 7, 6, 5, 0, 4, 3, 3, 2, 7, 4, 1, 7, 5, 4, 0, 1, 0, 7, 6, 2, 2, 4, 7, 4, 0, 5, 2, 5, 9, 5, 1, 1, 3, 4, 5, 2, 3, 8, 8, 6, 9, 1, 7, 8, 9, 4, 5, 9, 9, 9, 2, 2, 3, 1, 2, 8, 6, 2, 7, 1, 1, 4, 7, 6, 7, 8, 6, 0, 2, 6, 3, 3, 6, 7, 3, 1, 7, 1, 4, 2, 9, 8, 9, 4, 7, 7, 8, 9, 8, 0, 4, 0, 0, 7
OFFSET
0,2
COMMENTS
This constant is a transcendental number (Margolius, 2002; Smith, 2003). - Amiram Eldar, Aug 13 2020
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003. See pp. 430-433.
LINKS
Jonathan M. Borwein and Roland Girgensohn, Addition Theorems and Binary Expansions, Canadian Journal of Mathematics, Vol. 47, No. 2 (1995), pp. 262-273.
Barbara H. Margolius, Plouffe's Constant is Transcendental, unpublished note, 2002.
Simon Plouffe, The computation of certain numbers using a ruler and compass, Journal of Integer Sequences, Vol. 1 (1998), Article 98.1.3.
Eric Weisstein's World of Mathematics, Plouffe's Constants
EXAMPLE
0.14758...
MATHEMATICA
RealDigits[ArcTan[1/2]/Pi, 10, 100][[1]] (* Amiram Eldar, Aug 13 2020 *)
PROG
(PARI) atan(1/2)/Pi \\ Michel Marcus, Jul 29 2015
CROSSREFS
Sequence in context: A357483 A011092 A358924 * A248867 A199441 A196566
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Jul 12 2003
STATUS
approved