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A261409 Curvatures in a certain bounded, integral, primitive Soddy sphere packing. 2
-11, 21, 25, 27, 28, 34, 36, 40, 42, 43, 46, 48, 49, 51, 54, 57, 61, 63, 64, 67, 69, 70, 72, 73, 75, 78, 79, 81, 82, 84, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A three-dimensional Apollonian packing.

LINKS

Table of n, a(n) for n=1..31.

Nicolas Hannachi, Illustration of this packing, showing some of the initial terms [Fig. 2b in Kontorovich (2012), used with permission]

Nicolas Hannachi, Des cercles tangents et des sphères tangentes

Alex Kontorovich, The local-global principle for integral Soddy sphere packings, arXiv:1208.5441, 2012.

CROSSREFS

Cf. A261410.

Sequence in context: A360372 A350766 A189226 * A195100 A125164 A101223

Adjacent sequences: A261406 A261407 A261408 * A261410 A261411 A261412

KEYWORD

sign,more

AUTHOR

N. J. A. Sloane, Aug 23 2015

STATUS

approved

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Last modified March 21 17:39 EDT 2023. Contains 361408 sequences. (Running on oeis4.)