OFFSET
1,1
COMMENTS
Total number of walks as counted in A001411 that have an axis of symmetry, either parallel to an axis or at a 45-degree angle (the latter only possible for even n).
LINKS
Bert Dobbelaere, Table of n, a(n) for n = 1..60
Bert Dobbelaere, Illustration of initial terms
Brian Hayes, How to avoid yourself, American Scientist 86 (1998) 314-319.
MATHEMATICA
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
Bert Dobbelaere, Jan 06 2019
STATUS
approved