A105262 - cp's OEIS frontend

A105262 a(n)=number of tilings of a 4 X n rectangle using tiles that are either 1 X 1 squares or trominoes (here by a tromino we mean a 2 X 2 square with the upper right 1 X 1 square removed; no rotations allowed).

n	a(n)
0	1
1	1
2	5
3	13
4	42
5	126
6	387
7	1180
8	3606
9	11012
10	33636
11	102733
12	313781
13	958384
14	2927209
15	8940617
16	27307465
17	83405605
18	254747014
19	778077690
20	2376494563
21	7258563604
22	22169941574
23	67713990832
24	206819875428
25	631693101321
26	1929389878185

[1, 1, 5, 13, 42, 126, 387, 1180, 3606, 11012, 33636, 102733, 313781, 958384, 2927209, 8940617, 27307465, 83405605, 254747014, 778077690, 2376494563, 7258563604, 22169941574, 67713990832, 206819875428, 631693101321, 1929389878185]

cp's OEIS Frontend

A105262 a(n)=number of tilings of a 4 X n rectangle using tiles that are either 1 X 1 squares or trominoes (here by a tromino we mean a 2 X 2 square with the upper right 1 X 1 square removed; no rotations allowed).

Table of values

List of values