A178781 - OEIS

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A178781

Expansion of the polynomial (x^9-1)*(x^7-1)*(x^6-1)*(x^5-1)*(x^4-1)*(x^3-1)*(x-1) in increasing powers of x.

-1, 1, 0, 1, 0, 0, 0, -1, -1, 0, -1, 0, 1, 0, 2, 0, 1, 0, 0, -1, 0, -2, 0, -1, 0, 1, 0, 1, 1, 0, 0, 0, -1, 0, -1, 1

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OFFSET

0,15

COMMENTS

q^63*(q^18-1)*(q^14-1)*(q^12-1)*(q^10-1)*(q^8-1)*(q^6-1)*(q^2-1) is the order of the simple group E_7(q), if q is a prime power.

The x-polynomial f(x) and the q-polynomial g(q) are such that g(q) = q^63*f(q^2) - Jean-François Alcover, Aug 25 2022

REFERENCES

R. L. Griess, Jr., Twelve Sporadic Groups, Springer, 1998; see p. 169.

LINKS

Table of n, a(n) for n=0..35.

PROG

(PARI) Vecrev((x^9-1)*(x^7-1)*(x^6-1)*(x^5-1)*(x^4-1)*(x^3-1)*(x-1)) \\ Michel Marcus, Aug 25 2022

CROSSREFS

Cf. A008869, A178795.

Sequence in context: A281455 A284500 A281458 * A287174 A080843 A287112

Adjacent sequences: A178778 A178779 A178780 * A178782 A178783 A178784

KEYWORD

sign,fini,full,easy

AUTHOR

N. J. A. Sloane, Dec 26 2010

STATUS

approved