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A248571 Number of connected irreducible digital images of n points up to homotopy equivalence. 3

%I

%S 1,0,0,0,1,1,3,28,547

%N Number of connected irreducible digital images of n points up to homotopy equivalence.

%C "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.

%H J. Haarmann, M. Murphy, C. Peters, and P. C. Staecker, <a href="http://arxiv.org/abs/1408.2584">Homotopy equivalence of finite digital images</a>, arXiv:1408.2584 [math.GN], 2014.

%H P. C. Staecker, <a href="http://arxiv.org/abs/1502.06236">Some enumerations of binary digital images</a>, arXiv:1502.06236 [math.CO], 2015.

%K nonn,more,hard

%O 1,7

%A _P. Christopher Staecker_, Oct 13 2014

%E a(8)-a(9) from _P. Christopher Staecker_, Feb 24 2015

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Last modified January 27 16:10 EST 2022. Contains 350608 sequences. (Running on oeis4.)