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A101464
Decimal expansion of sqrt(2-sqrt(2)), edge length of a regular octagon with circumradius 1.
8
7, 6, 5, 3, 6, 6, 8, 6, 4, 7, 3, 0, 1, 7, 9, 5, 4, 3, 4, 5, 6, 9, 1, 9, 9, 6, 8, 0, 6, 0, 7, 9, 7, 7, 3, 3, 5, 2, 2, 6, 8, 9, 1, 2, 4, 9, 7, 1, 2, 5, 4, 0, 8, 2, 8, 6, 7, 6, 0, 1, 2, 7, 1, 2, 5, 5, 0, 9, 2, 0, 6, 7, 9, 2, 0, 1, 7, 9, 3, 8, 4, 4, 7, 4, 0, 2, 7, 5, 7, 0, 6, 8, 4, 5, 6, 7, 0, 9, 4, 2, 9, 6, 8, 4, 8
OFFSET
0,1
LINKS
Eric Weisstein's World of Mathematics, Octagon.
FORMULA
Equals i^(3/4) + i^(-3/4). - Gary W. Adamson, Jul 07 2022
Equals 2*sin(Pi/8) = 2*A182168. - Amiram Eldar, Apr 06 2023
Equals Product_ {k >= 0} ((8*k - 2)*(8*k + 10))/((8*k - 5)*(8*k + 13)). - Antonio GraciĆ” Llorente, Mar 11 2024
EXAMPLE
0.765366864730179543456919968060797733522689124971254082867601271255092067920...
MATHEMATICA
RealDigits[Sqrt[2-Sqrt[2]], 10, 120][[1]] (* Harvey P. Dale, Jun 22 2011 *)
CROSSREFS
Cf. A179260 (sqrt(2+sqrt(2))), A182168.
Sequence in context: A244921 A372951 A334380 * A072558 A022963 A023449
KEYWORD
cons,nonn
AUTHOR
Jun Mizuki (suzuki32(AT)sanken.osaka-u.ac.jp), Jan 20 2005
STATUS
approved