A245720 Decimal expansion of the mean cluster density for bond percolation on the triangular lattice.

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

Offset: 0

Author

Jean-François Alcover, Jul 30 2014

Keywords

• nonn
• cons

Examples

			0.11184427528454969567534433605161118038275119441321220145828...
		

References

• Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.18 Percolation Cluster Density Constants, p. 373.

Crossrefs

Cf. A130880.

Programs

Mathematica

RealDigits[35/4 - 3/(2*Sin[Pi/18]), 10, 104] // First

PARI

35/4 - 3/(2*sin(Pi/18)) \\ Stefano Spezia, May 17 2025

Formula

35/4 - 3/p_c, where p_c = A130880 = 2*sin(Pi/18) is the critical probability.