A197464 Number of fixed poly-[4.6.12]-tiles (holes allowed) with n cells (division into triangles is significant).

12, 18, 36, 75, 168, 386, 888, 2079, 4960, 11988, 29280, 72145, 179112, 447636, 1124956, 2840097, 7197780, 18301738, 46669404, 119308938, 305704584, 784938678, 2019335340, 5204309886, 13435321764, 34738762062, 89952855848

Offset: 1

Author

Joseph Myers, Oct 15 2011

Keywords

• hard
• nonn

References

• Branko Gruenbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Sections 2.7, 6.2 and 9.4.

Crossrefs

Cf. A197462, A197463.

Extensions

a(20)-a(26) from Aaron N. Siegel, Jun 03 2022

a(27) from Johann Peters, Dec 16 2024