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A348231
Coordination sequence for Wilkinson's 123-circle packing with respect to a circle of radius 3.
3
1, 8, 16, 28, 32, 48, 48, 68, 64, 88, 80, 108, 96, 128, 112, 148, 128, 168, 144, 188, 160, 208, 176, 228, 192, 248, 208, 268, 224, 288, 240, 308, 256, 328, 272, 348, 288, 368, 304, 388, 320, 408, 336, 428, 352, 448, 368, 468, 384, 488, 400, 508, 416, 528, 432
OFFSET
0,2
COMMENTS
See A348227 for much more information about this structure.
FORMULA
G.f. = (1 + 8*q + 14*q^2 + 12*q^3 + q^4)/(1 - q^2)^2. [This has not yet been officially proved, but it will follow from the "coloring book" method in the same way that the g.f. for A348227 was established.]
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 08 2021
EXTENSIONS
More terms from Rémy Sigrist, Oct 09 2021
STATUS
approved