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A089989 revision #6

A089989

5^(n^2+2n+1)*Product_{j=1..n} (25^j-1).

5, 15000, 29250000000, 35703281250000000000, 27239372138671875000000000000000, 12988743471794208526611328125000000000000000000, 3870947187719439049405530095100402832031250000000000000000000000, 721020100095350865678782984846420731628313660621643066406250000000000000000000000000

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OFFSET

0,1

COMMENTS

The order of the p-Clifford group for an odd prime p is a*p^(n^2+2n+1)*Product_{j=1..n} (p^(2*j)-1), where a = gcd(p+1,4).

LINKS

Table of n, a(n) for n=0..7.

G. Nebe, E. M. Rains and N. J. A. Sloane, Self-Dual Codes and Invariant Theory, Springer, Berlin, 2006.

CROSSREFS

Cf. A001309, A003956.

Cf. A092299 and A092301 (p=3), A092300 and A089989 (p=5), A090768 and A090769 (p=7), A090770 (p=2, although this is the wrong formula in that case).

Sequence in context: A368067 A364691 A367943 * A219011 A297482 A185686

Adjacent sequences: A089986 A089987 A089988 * A089990 A089991 A089992

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 10 2004

STATUS

approved