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A157223
Number of primitive inequivalent oblique sublattices of centered rectangular lattice of index n.
2
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
OFFSET
1,4
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
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Feb 25 2009
EXTENSIONS
New name and more terms from Andrey Zabolotskiy, May 09 2018
STATUS
approved