OFFSET
1,2
COMMENTS
From Walter Trump, Dec 15 2022: (Start)
a(n) is the number of fully symmetric dissections of an n X n square into squares with integer sides.
Conjecture: For n>3 the number of dissections is a multiple of 4. (End)
LINKS
Christopher Hunt Gribble, C++ program for A226978, A226979, A226980, A226981, A227004
Walter Trump, Example for n=19
FORMULA
EXAMPLE
For n=5, there are 4 dissections where the orbits under the symmetry group of the square, D4, have 1 element.
For n=4, 3 dissections divide the square into uniform subsquares (of sizes 1, 2 and 4 respectively), and this is the 4th:
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CROSSREFS
KEYWORD
nonn,more
AUTHOR
Christopher Hunt Gribble, Jun 25 2013
EXTENSIONS
a(8)-a(12) from Ed Wynn, Apr 02 2014
a(13)-a(25) from Walter Trump, Dec 15 2022
STATUS
approved