|
Search: id:A056267
|
|
|
| A056267 |
|
Number of primitive (aperiodic) words of length n which contain exactly two different symbols. |
|
+0
4
|
|
| 0, 2, 6, 12, 30, 54, 126, 240, 504, 990, 2046, 4020, 8190, 16254, 32730, 65280, 131070, 261576, 524286, 1047540, 2097018, 4192254, 8388606, 16772880, 33554400, 67100670, 134217216, 268419060, 536870910, 1073708010, 2147483646
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia.
|
|
FORMULA
|
sum mu(d)*A000918(n/d) where d|n and n>0.
|
|
CROSSREFS
|
Cf. A000079, A000918, A027375.
Cf. A038199.
Sequence in context: A081375 A024701 A038199 this_sequence A133996 A080742 A005417
Adjacent sequences: A056264 A056265 A056266 this_sequence A056268 A056269 A056270
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Marks R. Nester (nesterm(AT)dpi.qld.gov.au)
|
|
EXTENSIONS
|
Corrected and extended by Franklin T. Adams-Watters and T. D. Noe (noe(AT)sspectra.com), Oct 25 2006
|
|
|
Search completed in 0.002 seconds
|
