id:A104955 - OEIS Search Results

Search: id:A104955

Displaying 1-1 of 1 results found.

page 1

Decimal expansion of the area of the regular 5-gon (pentagon) of circumradius = 1.

+0
4

2, 3, 7, 7, 6, 4, 1, 2, 9, 0, 7, 3, 7, 8, 8, 3, 9, 3, 0, 2, 9, 1, 0, 9, 8, 3, 3, 3, 4, 4, 8, 4, 5, 5, 3, 5, 8, 5, 1, 4, 2, 4, 6, 5, 8, 5, 3, 1, 4, 3, 7, 5, 5, 5, 6, 1, 1, 8, 2, 6, 4, 1, 1, 1, 0, 7, 5, 3, 8, 2, 9, 2, 5, 2, 1, 2, 9, 8, 3, 7, 5, 4, 2, 9, 6, 9, 8, 2, 0, 2, 7, 4, 2, 7, 0, 2, 8, 4, 5, 4, 1, 8, 9, 7, 4 (list; cons; graph; listen)

	OFFSET	`1,1`
	COMMENT	`Equivalently, the area in the complex plane of the smallest convex set containing all order-5 roots of unity.`
	LINKS	`Eric Weisstein et al., "Root of Unity."` `Eric Weisstein's World of Mathematics, "de Moivre Number."`
	FORMULA	`(5*Sqrt[(5 + Sqrt[5])/2])/4`
	EXAMPLE	`2.3776412907378839302910983334484553585142465853143755561182641110753829252129837542969820274270284541897492938785075105224676655...`
	MATHEMATICA	`Floor[n/2]Sin[(2Pi)/n] - Sin[(4PiFloor[n/2])/n]/2 /. n -> 5`
	CROSSREFS	`Cf. A104954, A104956, A104957.` `Sequence in context: A070964 A111075 A011372 this_sequence A011161 A027672 A104138` `Adjacent sequences: A104952 A104953 A104954 this_sequence A104956 A104957 A104958`
	KEYWORD	`nonn,cons`
	AUTHOR	`Joseph Biberstine (jrbibers(AT)indiana.edu), Mar 30 2005`

page 1

Search completed in 0.002 seconds

Last modified November 25 20:09 EST 2009. Contains 167514 sequences.

AT&T Labs Research