OFFSET
1,3
COMMENTS
This sequence enumerates a subset of the polyominoes enumerated by A056877.
LINKS
John Mason, Table of n, a(n) for n = 1..50
FORMULA
EXAMPLE
a(2)=1 because of the 2 by 4 octomino.
CROSSREFS
KEYWORD
nonn
AUTHOR
John Mason, Feb 05 2022
STATUS
approved