A331140 Number of different coincidence site lattices of index n in lattice Z^4.

1, 1, 16, 0, 36, 16, 64, 0, 152, 36, 144, 0, 196, 64, 576, 0, 324, 152, 400, 0, 1024, 144, 576, 0, 912, 196, 1392, 0, 900, 576, 1024, 0, 2304, 324, 2304, 0, 1444, 400, 3136, 0, 1764, 1024, 1936, 0, 5472, 576, 2304, 0, 3152, 912, 5184, 0, 2916, 1392, 5184, 0

Offset: 1

Author

N. J. A. Sloane, Jan 12 2020

Keywords

• nonn
• mult

Links

• Michael Baake and Peter Zeiner, Coincidences in 4 dimensions, Phil. Mag. 88 (2008), 2025-2032; arXiv:0712.0363 [math.MG]. See end of Section 2.2.

Crossrefs

Cf. A031361, A331139, A331141, A331142.

Formula

a(2k-1) = a(4k-2) = A331139(k), a(4k) = 0. - Andrey Zabolotskiy, Jan 29 2020

Extensions

Name corrected, a(2) corrected, and terms a(18) and beyond added by Andrey Zabolotskiy, Jan 29 2020