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A135639 a(n) = 839*n. 4
0, 839, 1678, 2517, 3356, 4195, 5034, 5873, 6712, 7551, 8390, 9229, 10068, 10907, 11746, 12585, 13424, 14263, 15102, 15941, 16780, 17619, 18458, 19297, 20136, 20975, 21814, 22653, 23492, 24331, 25170, 26009, 26848, 27687, 28526 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The 146th prime number (839) and some of its multiples are related to the exceptional Lie group E_8 calculation because the result is a matrix with 453060 rows and columns. The size of the matrix is the member a(540)=453060 of this sequence. The number 839 is the largest prime factor of 453060 because we can write 2*2*3*3*3*5*839=453060. The number of entries of the matrix is the member a(244652400)=453060*453060=205263363600.

REFERENCES

American Institute of Mathematics, <a href="http://aimath.org/E8">Mathematicians Maps E_8</a>.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (2,-1).

FORMULA

From G. C. Greubel, Oct 25 2016: (Start)

a(n) = 839*n.

a(n) = 2*a(n-1) - a(n-2).

G.f.: (839*x)/(1 - x)^2.

E.g.f.: 839*x*exp(x). (End)

EXAMPLE

a(1)=839. a(540)=540*839=453060. a(244652400)=244652400*839=205263363600.

MATHEMATICA

839Range[0, 40] (* Harvey P. Dale, Sep 13 2011 *)

LinearRecurrence[{2, -1}, {0, 839}, 25] (* G. C. Greubel, Oct 25 2016 *)

CROSSREFS

Cf. A134888, A135631.

Sequence in context: A167603 A202716 A118380 * A158401 A156937 A135640

Adjacent sequences:  A135636 A135637 A135638 * A135640 A135641 A135642

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol, Nov 27 2007, Nov 29 2007

STATUS

approved

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Last modified December 8 06:50 EST 2016. Contains 278902 sequences.