|
Search: id:A060688
|
|
|
| A060688 |
|
Number of dissimilar ternary square-free words of length n+1. |
|
+0
3
|
|
| 1, 2, 3, 5, 7, 10, 13, 18, 24, 34, 44, 57, 76, 103, 133, 174, 232, 305, 398, 530, 691, 903, 1172, 1533, 1982, 2581, 3370, 4404, 5737, 7477, 9741, 12687, 16546, 21586, 28091
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
cycle b-> c-> b and a-> b-> c-> a to get 6 similar words in A006156(n+2)
|
|
REFERENCES
|
N. Wirth, Systematisches Programmieren, 1975, ch. 15.4, table 15.68
|
|
EXAMPLE
|
ab~ac (cycle b,c), ab~bc~ca and ac~ba~cb (cycle a,b,c) => a(1) = 6/6 = 1
|
|
CROSSREFS
|
a(n) := A006156(n+2)/6.
Sequence in context: A118199 A088318 A038083 this_sequence A005691 A035954 A023192
Adjacent sequences: A060685 A060686 A060687 this_sequence A060689 A060690 A060691
|
|
KEYWORD
|
nonn,more
|
|
AUTHOR
|
Frank Ellermann (Frank.Ellermann(AT)t-online.de), Apr 19 2001
|
|
|
Search completed in 0.002 seconds
|
