login
A259087
Number of n-celled polyominoes which are of rectangular but not square type.
2
0, 1, 1, 4, 6, 28, 83, 289, 1030, 3860, 14154, 53222, 202001, 771255, 2945803, 11304541, 43564276, 168413249, 652292925, 2531493604, 9845752518, 38372748112
OFFSET
1,4
LINKS
T. R. Parkin, L. J. Lander, and D. R. Parkin, Polyomino Enumeration Results, presented at SIAM Fall Meeting, 1967, and accompanying letter from T. J. Lander (annotated scanned copy). See page 21. The 15th entry is not included because their value for A000105(15) was incorrect.
FORMULA
a(n)+A259088(n) = A000105(n).
CROSSREFS
Sequence in context: A122113 A093815 A142859 * A364737 A056221 A046849
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Jun 18 2015
EXTENSIONS
a(15)-a(17) computed from A000105-A259088 by Jean-François Alcover, Dec 30 2019
a(18)-a(22) from John Mason, Nov 19 2021
STATUS
approved