|
Search: id:A055267
|
|
|
| A055267 |
|
a(n)=3a(n-1)-a(n-2); a(0)=1, a(1)=7. |
|
+0 3
|
|
| 1, 7, 20, 53, 139, 364, 953, 2495, 6532, 17101, 44771, 117212, 306865, 803383, 2103284, 5506469, 14416123, 37741900, 98809577, 258686831, 677250916, 1773065917, 4641946835, 12152774588, 31816376929, 83296356199
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
REFERENCES
|
I. Adler, Three Diophantine equations - Part II, Fib. Quart., 7 (1969), pps. 181-193.
A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pps. 122-125, 194-196.
E. I. Emerson, Recurrent Sequences in the Equation DQ^2=R^2+N, Fib. Quart.,7 (1969), pps. 231-242.
|
|
LINKS
|
Index entries for sequences related to linear recurrences with constant coefficients
Tanya Khovanova, Recursive Sequences
|
|
FORMULA
|
a(n)={7*[((3+sqrt(5))/2)^n-((3-sqrt(5))/2)^n]-[((3+sqrt(5))/2)^(n-1)-((3-sqrt(5))/2)^(n-1)]}/sqrt(5).
|
|
EXAMPLE
|
G.f.=(1+4x)/(1-3x+x^2)
|
|
CROSSREFS
|
Cf. A054492 and A054486.
Adjacent sequences: A055264 A055265 A055266 this_sequence A055268 A055269 A055270
Sequence in context: A007044 A047862 A048755 this_sequence A009370 A009372 A051102
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Barry E. Williams, May 09 2000
|
|
|
Search completed in 0.002 seconds
|