A336267 Number of free polyominoes of width 3 and height n.

1, 6, 24, 181, 941, 4662, 23691, 119271, 603760, 3050402, 15428576, 78004550, 394462578, 1994595585, 10086050889, 51001111356, 257894037378, 1304071170194, 6594196094078, 33344335235915, 168609627579175, 852594638783225, 4311246376730011

Offset: 1

Author

Jean-Luc Manguin, Jul 15 2020

Keywords

• nonn

Comments

The sequence can be generated using a series of recursive formulas in a fashion similar to A353067. - John Mason, Nov 04 2022

Examples

			a(2)=6, bounding box 2 X 3 as in A335711.
		

Links

• John Mason, Table of n, a(n) for n = 1..400

Crossrefs

Cf. A268371, A335711, A353067.

Extensions

More terms from John Mason, Nov 04 2022