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A166530 Decimal expansion of exp(4*Pi*sqrt(163)) (or A060295^4). 5
4, 7, 5, 0, 7, 7, 8, 7, 3, 0, 8, 2, 5, 1, 7, 7, 7, 2, 5, 4, 6, 3, 9, 2, 0, 9, 4, 8, 9, 0, 9, 7, 2, 6, 6, 1, 8, 2, 1, 4, 4, 9, 1, 7, 1, 8, 0, 3, 9, 4, 7, 1, 3, 6, 6, 3, 1, 8, 7, 4, 7, 4, 0, 6, 3, 6, 8, 7, 9, 2, 0, 0, 0, 0, 0, 0, 3, 0, 8, 4, 6, 4, 3, 2, 2, 1, 2, 9, 9, 8, 1, 1, 8, 0, 1, 8, 7, 9, 9, 6, 2, 0, 0, 0, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

70,1

COMMENTS

Near-integer obtained by taking Ramanujan's constant e^(Pi*sqrt(163)) to the fourth power.

REFERENCES

Henri Cohen, 'A Course in Computational Algebraic Number Theory', Springer-Verlag Berlin Heidelberg New-York 1996, p. 383.

LINKS

Table of n, a(n) for n=70..174.

MathOverflow, Why are powers of exp(Pi*sqrt(163)) almost integers?

Eric Weisstein's World of Mathematics, Almost Integer

Wikipedia, Heegner number

EXAMPLE

exp^(4*Pi*sqrt(163)) = 47507787308251777254639209489097266182144917180394713663187474063...

MATHEMATICA

RealDigits[Exp[Pi Sqrt[163]]^4, 10, 120][[1]]  (* Harvey P. Dale, Apr 20 2011 *)

PROG

(PARI) exp(4*Pi*sqrt(163)) \\ Charles R Greathouse IV, Nov 12 2014

CROSSREFS

Cf. A166528, A166529, A166531, A166532.

Sequence in context: A339948 A270136 A269756 * A011518 A132265 A175348

Adjacent sequences:  A166527 A166528 A166529 * A166531 A166532 A166533

KEYWORD

nonn,cons

AUTHOR

Mark A. Thomas, Oct 16 2009

STATUS

approved

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Last modified December 1 11:07 EST 2021. Contains 349429 sequences. (Running on oeis4.)