A247446 Decimal expansion of Pi*sqrt(3)/16.

3, 4, 0, 0, 8, 7, 3, 8, 0, 7, 9, 3, 9, 1, 5, 8, 4, 6, 9, 8, 6, 3, 8, 9, 6, 7, 3, 3, 0, 7, 9, 0, 4, 1, 9, 9, 8, 0, 3, 2, 6, 2, 4, 2, 1, 5, 1, 7, 3, 8, 8, 8, 5, 7, 9, 1, 9, 3, 5, 3, 4, 2, 5, 3, 8, 5, 2, 7, 3, 0, 9, 6, 4, 6, 1, 1, 9, 1, 3, 5, 3, 1, 9, 0, 7, 7, 3, 4, 3, 5, 2, 8, 9, 7, 6, 1, 2, 8, 1, 6, 6, 0, 5, 4, 1, 7

Offset

0,1

Comments

The atomic packing factor (APF) of the diamond cubic crystal lattice and the smallest APF among all crystallographic lattices filled by spheres of the same diameter. The APF of the body-centered-cubic (bcc) lattice packed with spheres of the same diameter is twice this value (see Examples). For other crystal lattices, see the cross-refs.

Links

Stanislav Sykora, Table of n, a(n) for n = 0..2000

Steve Sque, Structure of Diamond (adapted from 2005 thesis)

Wikipedia, Diamond cubic

Wikipedia, Atomic packing factor

Index entries for transcendental numbers

Example

0.340087380793915846986389673307904199803262421517388857919353425385273...
APF of the bcc lattice packed with spheres of the same diameter:
0.680174761587831693972779346615808399606524843034777715838706850770546...

Mathematica

RealDigits[Pi*Sqrt[3]/16, 10, 120][[1]] (* Vaclav Kotesovec, Oct 04 2014 *)

Prog

(PARI) Pi*sqrt(3)/16

Crossrefs

Cf. APF's of other crystal lattices: A093825 (hcp,fcc), A019673 (simple cubic).

Sequence in context: A378408 A155061 A322016 * A131099 A098800 A087666

Adjacent sequences: A247443 A247444 A247445 * A247447 A247448 A247449

Keyword

nonn,cons,easy

Author

Stanislav Sykora, Sep 29 2014

Status

approved