A277237 - cp's OEIS frontend

A277237 Number of strings of length n composed of symbols from the circular list [1,2,3,4,5,6] such that adjacent symbols in the string must be adjacent in the list. No runs of length 2 or more are allowed for symbols 1, 3 and 5.

n	a(n)
0	1
1	6
2	15
3	39
4	99
5	255
6	651
7	1671
8	4275
9	10959
10	28059
11	71895
12	184131
13	471711
14	1208235
15	3095079
16	7928019
17	20308335
18	52020411
19	133253751
20	341335395
21	874350399
22	2239691979
23	5737093575
24	14695861491
25	37644235791
26	96427681755
27	247004624919
28	632715351939
29	1620733851615

[1, 6, 15, 39, 99, 255, 651, 1671, 4275, 10959, 28059, 71895, 184131, 471711, 1208235, 3095079, 7928019, 20308335, 52020411, 133253751, 341335395, 874350399, 2239691979, 5737093575, 14695861491, 37644235791, 96427681755, 247004624919, 632715351939, 1620733851615]

cp's OEIS Frontend

A277237 Number of strings of length n composed of symbols from the circular list [1,2,3,4,5,6] such that adjacent symbols in the string must be adjacent in the list. No runs of length 2 or more are allowed for symbols 1, 3 and 5.

Table of values

List of values