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A157223

Number of primitive inequivalent oblique sublattices of centered rectangular lattice of index n.

0, 1, 1, 2, 2, 5, 3, 4, 5, 8, 5, 10, 6, 11, 10, 10, 8, 17, 9, 16, 14, 17, 11, 20, 14, 20, 17, 22, 14, 34, 15, 22, 22, 26, 22, 34, 18, 29, 26, 32, 20, 46, 21, 34, 34, 35, 23, 44, 27, 44, 34, 40, 26, 53, 34, 44, 38, 44, 29, 68, 30, 47, 46, 46, 40, 70, 33, 52, 46

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OFFSET

1,4

LINKS

Table of n, a(n) for n=1..69.

John S. Rutherford, Sublattice enumeration. IV. Equivalence classes of plane sublattices by parent Patterson symmetry and colour lattice group type, Acta Cryst. (2009). A65, 156-163. [See Table 4.]

FORMULA

a(n) = (A001615(n) - A060594(n))/2. - Andrey Zabolotskiy, May 09 2018

CROSSREFS

Cf. A060594 (primitive mirror-symmetric sublattices), A145390 (all mirror-symmetric sublattices), A145391 (all sublattices), A001615, A304182.

Sequence in context: A308515 A361328 A128134 * A174608 A130327 A224361

Adjacent sequences: A157220 A157221 A157222 * A157224 A157225 A157226