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A248571
Number of connected irreducible digital images of n points up to homotopy equivalence.
3
1, 0, 0, 0, 1, 1, 3, 28, 547
OFFSET
1,7
COMMENTS
"Irreducible" means not homotopy equivalent to any digital image of fewer points. The terms are nonzero for all n>4, and are believed to be strictly increasing for n>6.
LINKS
J. Haarmann, M. Murphy, C. Peters, and P. C. Staecker, Homotopy equivalence of finite digital images, arXiv:1408.2584 [math.GN], 2014.
P. C. Staecker, Some enumerations of binary digital images, arXiv:1502.06236 [math.CO], 2015.
CROSSREFS
Sequence in context: A192559 A161971 A156315 * A062497 A367391 A056066
KEYWORD
nonn,more,hard
AUTHOR
EXTENSIONS
a(8)-a(9) from P. Christopher Staecker, Feb 24 2015
STATUS
approved