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 A104954 Decimal expansion of the area of the regular 3-gon (triangle) of circumradius = 1. Note this is (1/2)*A104956. 4
 1, 2, 9, 9, 0, 3, 8, 1, 0, 5, 6, 7, 6, 6, 5, 7, 9, 7, 0, 1, 4, 5, 5, 8, 4, 7, 5, 6, 1, 2, 9, 4, 0, 4, 2, 7, 5, 2, 0, 7, 1, 0, 3, 9, 4, 0, 3, 5, 7, 7, 8, 5, 4, 7, 1, 0, 4, 1, 8, 5, 5, 2, 3, 4, 5, 8, 8, 9, 4, 9, 7, 6, 2, 6, 8, 1, 6, 0, 0, 0, 2, 7, 8, 1, 0, 8, 5, 9, 6, 4, 0, 0, 6, 7, 9, 3, 6, 4, 3, 1, 7, 5, 6, 7, 1 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Equivalently, the area in the complex plane of the smallest convex set containing all order-3 roots of unity. LINKS Eric Weisstein et al., "Root of Unity." Eric Weisstein's World of Mathematics, "de Moivre Number." FORMULA 3*Sqrt[3]/4 EXAMPLE 1.2990381056766579701455847561294042752071039403577854710418552345889497626816000278108596400679364317567196060615550272724774588... MATHEMATICA Floor[n/2]*Sin[(2*Pi)/n] - Sin[(4*Pi*Floor[n/2])/n]/2 /. n -> 3 CROSSREFS Cf. A104955, A104956, A104957. Sequence in context: A073927 A198358 A145427 * A244292 A011072 A175295 Adjacent sequences:  A104951 A104952 A104953 * A104955 A104956 A104957 KEYWORD nonn,cons AUTHOR Joseph Biberstine (jrbibers(AT)indiana.edu), Mar 30 2005 STATUS approved

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Last modified January 26 05:37 EST 2020. Contains 331273 sequences. (Running on oeis4.)