|
| |
|
|
A143373
|
|
Expansion of x / (1-x-2*x^3-2*x^5-x^7).
|
|
0
| |
|
|
1, 1, 1, 3, 5, 9, 17, 30, 55, 100, 181, 330, 599, 1088, 1978, 3593, 6529, 11864, 21556, 39169, 71171, 129319, 234978, 426961, 775801, 1409655, 2561384, 4654113, 8456664, 15366012, 27920509
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,4
|
|
|
COMMENTS
| A new 4 symbol polynomial of the Weaver telegraphic type ( simplified) : dot:x; dash:x^3; Letter space: x^2 ; Word space: x^4 ; p(y)=-1 - 2 y^2 - 2 y^4 - y^6 + y^7.
An alternative set of symbols would be:
dot:x;
dash:x^2;
Letter space: x^3 ;
Word space: x^4 ;
|
|
|
REFERENCES
| Claude Shannon and Warren Weaver, A Mathematical Theory of Communication, University of Illinois Press, Chicago, 1963, p37 - 38
|
|
|
LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (1,0,2,0,2,0,1).
|
|
|
EXAMPLE
| Weaver determinant:
Expand[FullSimplify[ExpandAll[y^7 *Det[{{-1, (1/y^3 + 1/y)}, {(1/y^4 + 1/y^2),1/y + 1/y^3 - 1}}]]]].
|
|
|
MATHEMATICA
| p[y_] = -1 - 2 y^2 - 2 y^4 - y^6 + y^7; q[x_] = ExpandAll[x^13*p[1/x]]; a = Table[SeriesCoefficient[Series[1/q[x], {x, 0, 30}], n], {n, 0, 30}]
|
|
|
CROSSREFS
| Cf. A122762.
Sequence in context: A018162 A077879 A078140 * A102475 A066173 A114322
Adjacent sequences: A143370 A143371 A143372 * A143374 A143375 A143376
|
|
|
KEYWORD
| nonn,uned
|
|
|
AUTHOR
| Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 22 2008
|
| |
|
|