A393824 a(n) is the number of unit cubes in the cubic lattice, divided by 8, that have 4 vertices strictly inside and 4 vertices strictly outside the sphere x^2 + y^2 + z^2 = n.

0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 0, 0, 3, 3, 3, 12, 9, 0, 1, 4, 4, 4, 9, 9, 9, 12, 6, 9, 12, 3, 6, 12, 12, 12, 12, 13, 16, 10, 7, 22, 16, 3, 9, 18, 21, 15, 18, 24, 21, 18, 15, 15, 18, 12, 12, 24, 24, 27, 25, 13, 19, 19, 25, 40, 37, 22, 15, 24, 21, 18, 27, 30, 27, 24, 18, 33, 39

Offset

0,8

Links

Hugo Pfoertner, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A393563, A393821-A393827.

Sequence in context: A069191 A175362 A189973 * A282866 A098445 A290696

Adjacent sequences: A393821 A393822 A393823 * A393825 A393826 A393827

Keyword

nonn

Author

Hugo Pfoertner, Mar 01 2026

Status

approved