OFFSET
1,4
COMMENTS
An orthoplex polyomino does not extend more than two units along any axis.
EXAMPLE
There are a(5)=5 orthoplex pentominoes: the two 3-D pentominoes that fit in a 2 X 2 X 2 box and the three 4-D pentominoes.
CROSSREFS
KEYWORD
hard,more,nice,nonn
AUTHOR
STATUS
approved