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A160515 Decimal expansion of the integer (640320^3 + 744)^2 *70^2 = 337736875876935471466319632507953926400. 3
3, 3, 7, 7, 3, 6, 8, 7, 5, 8, 7, 6, 9, 3, 5, 4, 7, 1, 4, 6, 6, 3, 1, 9, 6, 3, 2, 5, 0, 7, 9, 5, 3, 9, 2, 6, 4, 0, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

39,1

COMMENTS

640320^3 +744 is an integer which is very close to Ramanujan's constant e^pi{sqrt163} = 640320^3 +743.99999999999925 and 70^2 is related to the norm vector 0 of the hyperbolic version of the Leech lattice since 1^2+2^2+3^3...+22^2+23^2+24^2 = 70^2.

337736875876935471466319632507953926400 = 2^8*3^2*5^2*7^2*10939058860032031^2 and 10939058860032031 is a prime number which can be decomposed to 2^15*3^2*5^3*23^3*29^3 + 31.

REFERENCES

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, 3rd, 1999.

LINKS

Table of n, a(n) for n=39..77.

FORMULA

Equals product_{i=1..5} A160514(i).

CROSSREFS

Sequence in context: A000199 A201932 A161771 * A105670 A003817 A092474

Adjacent sequences:  A160512 A160513 A160514 * A160516 A160517 A160518

KEYWORD

nonn,cons,fini,full

AUTHOR

Mark A. Thomas, May 16 2009

EXTENSIONS

Partially edited by R. J. Mathar, May 30 2009

Edited by N. J. A. Sloane, Dec 24 2010

STATUS

approved

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Last modified April 24 13:28 EDT 2014. Contains 240983 sequences.