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A393009
a(n) is the sum of mutual Manhattan distances of the A000328(n) distinct grid points (x_i,y_i) in a square lattice such that x_i^2 + y_i^2 <= n^2.
1
0, 16, 192, 1456, 5416, 19168, 44000, 87840, 176840, 330640, 581600, 896568, 1326544, 2092136, 3023816, 4352128, 5828984, 7922344, 10514024, 13923280, 18216176, 22709264, 29145424, 36121112, 44259112, 55376432, 67366040, 81514856, 96903152, 115237224, 137454408
OFFSET
1,2
COMMENTS
The coordinates of the grid points are provided in the first A000328(n) terms of A305575 and A305576.
Comparison against A193452:
n a(n) m=A000328(n)
1 16 5 16
2 192 13 188
3 1456 29 1442
4 5416 49 5398
5 19168 81 19062
6 44000 113 43900
FORMULA
a(n) == 0 (mod 8).
a(n) >= A193452(A000328(n)).
CROSSREFS
Cf. A393008 (similar in 3D).
Sequence in context: A302298 A305773 A317122 * A230832 A305590 A232426
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Feb 03 2026
STATUS
approved