|
| |
|
|
A168418
|
|
a(n) = 9*n-a(n-1)-8 with n>1, a(1)=5.
|
|
2
|
|
|
|
5, 5, 14, 14, 23, 23, 32, 32, 41, 41, 50, 50, 59, 59, 68, 68, 77, 77, 86, 86, 95, 95, 104, 104, 113, 113, 122, 122, 131, 131, 140, 140, 149, 149, 158, 158, 167, 167, 176, 176, 185, 185, 194, 194, 203, 203, 212, 212, 221, 221, 230, 230, 239, 239, 248, 248, 257
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index to sequences with linear recurrences with constant coefficients, signature (1,1,-1).
|
|
|
FORMULA
|
a(n) = -(7/4)-(9/4)*(-1)^n+(9/2)*n. - Paolo P. Lava, Nov 27 2009
a(n) = A168213(n-1), n>1. G.f.: x*(5+4*x^2)/((1+x)*(x-1)^2). - R. J. Mathar, Jan 26 2010
|
|
|
MATHEMATICA
|
LinearRecurrence[{1, 1, -1}, {5, 5, 14}, 60] (* Vincenzo Librandi, Feb 27 2012 *)
|
|
|
PROG
|
(MAGMA) I:=[5, 5, 14]; [n le 3 select I[n] else Self(n-1)+Self(n-2)-Self(n-3): n in [1..60]]; // Vincenzo Librandi, Feb 28 2012
|
|
|
CROSSREFS
|
Sequence in context: A076903 A192987 A062367 * A061200 A050350 A196060
Adjacent sequences: A168415 A168416 A168417 * A168419 A168420 A168421
|
|
|
KEYWORD
|
nonn,easy
|
|
|
AUTHOR
|
Vincenzo Librandi, Nov 25 2009
|
|
|
STATUS
|
approved
|
| |
|
|
