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A128885
Number of closed orientable irreducible 3-manifolds of complexity n.
0
3, 2, 4, 7, 14, 31, 74, 175, 436, 1154, 3078, 8421, 23448, 66197
OFFSET
0,1
REFERENCES
S. Matveev, Algorithmic Topology and Classification of 3-Manifolds, Springer, 2003.
LINKS
Bruno Martelli, Complexity of 3-manifolds, arXiv:math/0405250 [math.GT], 2004-2005.
S. Matveev, Atlas of 3-manifolds. The data for n = 12 may be incomplete, showing only 23434 manifolds.
S. V. Matveev and V. V. Tarkaev, Recognition and tabulation of 3-manifolds up to complexity 13, Chebyshevskii Sbornik, 21 (2020), 290-300.
A. Yu. Vesnin, S. V. Matveev, and E. A. Fominykh, Complexity of 3-dimensional manifolds: exact values and estimates, Siberian Electronic Mathematical Reports, 8 (2011), 341-364 [in Russian]. Theorem 2.1 gives erroneous a(12) = 23452.
CROSSREFS
A005418 seems to enumerate lens spaces by complexity, see Martelli.
Cf. A174684.
Sequence in context: A376183 A102787 A014193 * A215335 A229976 A084695
KEYWORD
hard,more,nonn,changed
AUTHOR
Sergei Duzhin, Apr 19 2007
EXTENSIONS
Term 23434 added by Sergei Duzhin, Jan 28 2013
a(12) corrected and a(13) added from Matveev and Tarkaev by Andrei Zabolotskii, May 20 2026
STATUS
approved