|
|
A074602
|
|
a(n) = 2^n + 7^n.
|
|
4
|
|
|
2, 9, 53, 351, 2417, 16839, 117713, 823671, 5765057, 40354119, 282476273, 1977328791, 13841291297, 96889018599, 678223089233, 4747561542711, 33232930635137, 232630514118279, 1628413598172593, 11398895185897431
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,1
|
|
LINKS
|
|
|
FORMULA
|
a(n) = 7*a(n-1) - 2^n = 9*a(n-1) - 14*a(n-2).
G.f.: 1/(1-2*x) + 1/(1-7*x).
E.g.f.: e^(2*x) + e^(7*x). (End)
|
|
MATHEMATICA
|
Table[2^n + 7^n, {n, 0, 25}]
|
|
PROG
|
|
|
CROSSREFS
|
Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600 - A074624.
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|