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A242969 Decimal expansion of an Ising constant related to the hexagonal lattice. 2
1, 0, 2, 5, 0, 5, 9, 0, 9, 6, 4, 7, 1, 3, 1, 3, 2, 2, 0, 1, 7, 4, 4, 7, 3, 0, 0, 8, 3, 6, 4, 4, 7, 7, 7, 0, 2, 7, 8, 9, 9, 2, 5, 0, 0, 7, 6, 1, 1, 5, 4, 8, 7, 6, 0, 1, 5, 7, 5, 9, 9, 1, 7, 6, 1, 0, 7, 3, 3, 9, 2, 7, 5, 2, 9, 8, 5, 8, 6, 9, 0, 2, 1, 2, 6, 0, 7, 0, 1, 1, 3, 5, 6, 3, 3, 5, 6, 6, 0, 6 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.22 Lenz-Ising constants, p. 399.

LINKS

Table of n, a(n) for n=1..100.

FORMULA

3/4*log(2) + log(3)/2 + H/4, where H is defined in A242967.

EXAMPLE

1.0250590964713132201744730083644777...

MATHEMATICA

H = Sqrt[3]/(6*Pi)*PolyGamma[1, 1/6] - Pi/Sqrt[3] - Log[6]; 3/4*Log[2] + Log[3]/2 + H/4 // RealDigits[#, 10, 100]& // First

CROSSREFS

Cf. A242967, A242968.

Sequence in context: A123342 A196816 A058204 * A268886 A090625 A021403

Adjacent sequences:  A242966 A242967 A242968 * A242970 A242971 A242972

KEYWORD

nonn,cons

AUTHOR

Jean-Fran├žois Alcover, May 28 2014

STATUS

approved

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Last modified August 19 04:34 EDT 2019. Contains 326109 sequences. (Running on oeis4.)