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A045771 Number of similar sublattices of index n^2 in root lattice D_4. 1
1, 1, 8, 1, 12, 8, 16, 1, 41, 12, 24, 8, 28, 16, 96, 1, 36, 41, 40, 12, 128, 24, 48, 8, 97, 28, 176, 16, 60, 96, 64, 1, 192, 36, 192, 41, 76, 40, 224, 12, 84, 128, 88, 24, 492, 48, 96, 8, 177, 97 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Multiplicative with a(2^p) = 1, a(p^e) = (e+1)*p^e + (e+1)*p^e + (2*(1+(e*p-e-1)*p^e))/((p-1)^2), p>2. Christian G. Bower (bowerc(AT)usa.net) May 21, 2005.

LINKS

M. Baake and R. V. Moody, Similarity submodules and root systems in four dimensions, Canad. J. Math. (1999), 51 1258-1276.

J. H. Conway, E. M. Rains and N. J. A. Sloane, On the existence of similar sublattices, Canad. J. Math. 51 (1999), 1300-1306 (Abstract, pdf, ps).

Index entries for sequences related to D_4 lattice

Index entries for sequences related to sublattices

CROSSREFS

Cf. A035292.

Sequence in context: A032012 A092702 A070475 * A070488 A124906 A181762

Adjacent sequences:  A045768 A045769 A045770 * A045772 A045773 A045774

KEYWORD

nonn,mult

AUTHOR

Michael Baake (baake(AT)miles.math.ualberta.ca)

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Last modified February 15 07:21 EST 2012. Contains 205705 sequences.