OFFSET
1,3
LINKS
John Mason, Table of n, a(n) for n = 1..50 (This version corrects erroneous values from a(44) onwards in previous version)
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.
MATHEMATICA
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 18 2015
EXTENSIONS
a(5)-a(6) corrected and a(15)-a(28) from Andrew Howroyd, Dec 04 2018
a(29) and beyond from John Mason, Dec 22 2021
STATUS
approved