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A242967
Decimal expansion of H, an auxiliary constant used to evaluate some Ising-related constants on triangular and hexagonal lattices (negated).
6
1, 7, 6, 4, 2, 9, 7, 3, 3, 1, 3, 0, 8, 0, 2, 4, 3, 0, 3, 4, 4, 2, 9, 4, 8, 0, 4, 7, 6, 1, 6, 7, 0, 3, 0, 2, 3, 6, 1, 7, 8, 1, 4, 8, 8, 2, 8, 0, 0, 6, 9, 6, 2, 5, 2, 0, 1, 0, 3, 1, 9, 9, 1, 3, 2, 5, 8, 1, 2, 3, 5, 1, 1, 5, 1, 9, 5, 4, 4, 7, 2, 0, 6, 0, 5, 4, 1, 0, 3, 6, 3, 6, 3, 2, 9, 3, 8, 1, 5, 9, 6
OFFSET
0,2
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.22 Lenz-Ising constants, p. 400.
LINKS
Eric Weisstein's MathWorld, Digamma Function
FORMULA
sqrt(3)/(6*Pi)*psi'(1/6) - Pi/sqrt(3) - log(6), where psi' is the derivative of the digamma function.
EXAMPLE
-0.1764297331308024303442948047616703...
MATHEMATICA
Sqrt[3]/(6*Pi)*PolyGamma[1, 1/6] - Pi/Sqrt[3] - Log[6] // RealDigits[#, 10, 101]& // First
CROSSREFS
Sequence in context: A131184 A021933 A154730 * A228628 A131266 A258094
KEYWORD
nonn,cons
AUTHOR
STATUS
approved