login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A130880 Decimal expansion of 2*sin(Pi/18). 0
3, 4, 7, 2, 9, 6, 3, 5, 5, 3, 3, 3, 8, 6, 0, 6, 9, 7, 7, 0, 3, 4, 3, 3, 2, 5, 3, 5, 3, 8, 6, 2, 9, 5, 9, 2, 0, 0, 0, 7, 5, 1, 3, 5, 4, 3, 6, 8, 1, 3, 8, 7, 7, 4, 4, 7, 2, 4 (list; constant; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Also: a bond percolation threshold probability on the triangular lattice.

REFERENCES

S. R. Finch, Several constants arising in statistical mechanics, Annals Combinat. 3 (1999) p 323-335.

FORMULA

Equals 2*A019819=A019829/A019889.

EXAMPLE

0.34729635533386069770....

PROG

(PARI) 2*sin(Pi/18);

CROSSREFS

Cf. A019819.

Sequence in context: A166043 A021292 A105828 * A026248 A082089 A089961

Adjacent sequences:  A130877 A130878 A130879 * A130881 A130882 A130883

KEYWORD

cons,nonn

AUTHOR

R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 26 2007

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 15 16:21 EST 2012. Contains 205823 sequences.