|
| |
| |
|
|
|
2, 9, 41, 189, 881, 4149, 19721, 94509, 456161, 2215269, 10814201, 53022429, 260917841, 1287811989, 6371951081, 31591319949, 156882857921, 780119322309, 3883416742361, 19348364235069, 96466943268401, 481235204714229
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,1
|
|
|
FORMULA
| G.f.: 1/(1-4*x)+1/(1-5*x). E.g.f.: e^(4*x)+e^(5*x). [From Mohammad K. Azarian (azarian(AT)evansville.edu), Jan 11 2009]
a(n)=9*a(n-1)-20*a(n-2) with a(0)=2, a(1)=9 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jul 21 2010]
|
|
|
MATHEMATICA
| Table[4^n + 5^n, {n, 0, 25}]
|
|
|
CROSSREFS
| Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600 - A074624.
Sequence in context: A130767 A020698 A128752 * A181375 A152052 A192661
Adjacent sequences: A074608 A074609 A074610 * A074612 A074613 A074614
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 25 2002
|
| |
|
|
