OFFSET
1,7
COMMENTS
Rigid means that the identity map is not homotopic to any other map.
LINKS
P. C. Staecker, Some enumerations of binary digital images, arXiv:1502.06236 [math.CO], 2015 (see table p. 3).
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
P. Christopher Staecker, Feb 24 2015
STATUS
approved