|
|
A205493
|
|
Third row or column of table A205497.
|
|
1
|
|
|
1, 14, 109, 623, 2951, 12331, 47191, 169416, 579889, 1914226, 6144668, 19298724, 59579803, 181448918, 546629054, 1632497850, 4841448042, 14277423006, 41912838982, 122587133760, 357476552161, 1039922075888, 3019280091491, 8752184436454, 25337900299765
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
COMMENTS
|
See A205497 regarding association of this sequence with generating functions for the rows of the tabular form of A050446.
|
|
LINKS
|
|
|
FORMULA
|
Conjecture 1. a(n) = M_{n,3} = M_{3,n}, where M = A205497.
Conjecture 2. Let w=2*cos(Pi/9). Then lim_{n -> infinity) a(n+1)/a(n) = w^3-2*w = spectral radius of the 4 X 4 unit-primitive matrix (see [Jeffery]) A_{9,3} = [0,0,0,1; 0,0,1,1; 0,1,1,1; 1,1,1,1].
|
|
PROG
|
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|