OFFSET
1,1
COMMENTS
See A216730 for definitions.
I would very much like to have a formula or recurrence for this sequence.
Alternatively, the number of squares of length 2n over a binary alphabet having no proper prefix that is a square. Here by a square I mean a word of the form xx, where x is any word. - Jeffrey Shallit, Nov 29 2013
LINKS
Daniel Gabric, Jeffrey Shallit, Borders, Palindrome Prefixes, and Square Prefixes, arXiv:1906.03689 [cs.DM], 2019.
Daniel Gabric, Jeffrey Shallit, Borders, palindrome prefixes, and square prefixes, Info. Proc. Letters 165 (2021), 106027.
EXAMPLE
Taking the alphabet to be {2,3}, v = 32232 has curling number 1, but 2232.32232 has curling number 2, so is not counted here.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 27 2012
EXTENSIONS
a(31)-a(35) from N. J. A. Sloane, Oct 25 2012
STATUS
approved