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A218387 Decimal expansion of the spanning tree constant of the square lattice. 8
1, 1, 6, 6, 2, 4, 3, 6, 1, 6, 1, 2, 3, 2, 7, 5, 1, 2, 0, 5, 5, 3, 5, 3, 7, 8, 2, 5, 8, 7, 3, 5, 7, 9, 6, 7, 5, 4, 5, 6, 2, 6, 4, 6, 1, 5, 9, 4, 3, 3, 4, 9, 0, 8, 1, 0, 4, 4, 0, 0, 6, 2, 7, 6, 4, 4, 6, 9, 9, 0, 5, 4, 7, 5, 2, 1, 7, 5, 5, 4, 4, 6, 9, 0, 6, 5, 0, 7, 2, 9, 7, 2, 1, 2, 5, 3, 6, 2, 3, 5, 6, 3, 5, 8, 9, 1, 2, 1, 1, 1, 1, 5, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

Anthony J. Guttmann, Spanning tree generating functions and Mahler measure, arXiv:1207.2815 [math-ph], 2012.

FORMULA

Equals the product of A006752 by A088538.

EXAMPLE

1.1662436161232751205...

MAPLE

evalf(Catalan*4/Pi) ;

MATHEMATICA

RealDigits[4*Catalan/Pi, 10, 100][[1]] (* G. C. Greubel, Aug 23 2018 *)

PROG

(PARI) default(realprecision, 100); 4*Catalan/Pi \\ G. C. Greubel, Aug 23 2018

(MAGMA) R:= RealField(100); 4*Catalan(R)/Pi(R); // G. C. Greubel, Aug 23 2018

CROSSREFS

Cf. A006752 (Catalan), A088538 (4/Pi).

Sequence in context: A191504 A021155 A254245 * A178857 A003676 A033259

Adjacent sequences:  A218384 A218385 A218386 * A218388 A218389 A218390

KEYWORD

cons,easy,nonn

AUTHOR

R. J. Mathar, Oct 27 2012

STATUS

approved

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Last modified April 26 12:31 EDT 2019. Contains 322472 sequences. (Running on oeis4.)