

A102769


Decimal expansion of the volume of a dodecahedron with each edge of unit length.


9



7, 6, 6, 3, 1, 1, 8, 9, 6, 0, 6, 2, 4, 6, 3, 1, 9, 6, 8, 7, 1, 6, 0, 5, 3, 9, 2, 0, 2, 7, 9, 7, 3, 3, 4, 1, 2, 0, 2, 1, 0, 8, 2, 1, 2, 9, 3, 2, 0, 1, 7, 0, 0, 1, 7, 4, 7, 4, 0, 7, 0, 1, 7, 9, 4, 6, 8, 4, 1, 1, 6, 1, 9, 8, 6, 6, 1, 5, 8, 5, 7, 3, 9, 7, 5, 2, 2, 5, 2, 1, 4, 6, 6, 2, 8, 6, 8, 9, 8, 1
(list;
constant;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Equals 5*phi^3/(2*xi^2), phi being the golden ratio (A001622) and xi its associate (A182007).  Stanislav Sykora, Nov 23 2013


LINKS

Ivan Panchenko, Table of n, a(n) for n = 1..1000
Eric Weisstein's World of Mathematics, Dodecahedron
Wikipedia, Platonic solid


FORMULA

Equals (15 + 7 sqrt(5)) / 4.
Equals (sqrt(5)/2)*(phi)^4, where phi is the golden ratio.  G. C. Greubel, Jul 06 2017


EXAMPLE

7.663118960624631968716053920...


MAPLE

evalf((15+7*sqrt(5))/4, 100); # Wesley Ivan Hurt, Jan 29 2017


MATHEMATICA

RealDigits[(Sqrt[5]/2)*(GoldenRatio)^4, 10, 50][[1]] (* G. C. Greubel, Jul 06 2017 *)


PROG

(PARI) (7*sqrt(5)+15)/4 \\ Charles R Greathouse IV, Apr 25 2016


CROSSREFS

Cf. A001622 (phi), A182007 (phi associate), A020829 (regular tetrahedron volume), A131594 (regular octahedron volume), A102208 (regular icosahedron volume).
Sequence in context: A019859 A188736 A265304 * A031348 A247674 A109696
Adjacent sequences: A102766 A102767 A102768 * A102770 A102771 A102772


KEYWORD

nonn,cons


AUTHOR

Bryan Jacobs (bryanjj(AT)gmail.com), Feb 10 2005


STATUS

approved



