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

1, 0, 0, 0, 1, 1, 3, 28, 547

Offset: 1

Author

P. Christopher Staecker, Oct 13 2014

Keywords

• nonn
• more
• hard

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.

Extensions

a(8)-a(9) from P. Christopher Staecker, Feb 24 2015