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A176449
a(n) = 9*2^n - 2.
5
7, 16, 34, 70, 142, 286, 574, 1150, 2302, 4606, 9214, 18430, 36862, 73726, 147454, 294910, 589822, 1179646, 2359294, 4718590, 9437182, 18874366, 37748734, 75497470, 150994942, 301989886, 603979774, 1207959550, 2415919102
OFFSET
0,1
FORMULA
a(n) = 2*(a(n-1)+1) with a(0) = 7.
a(n) = 3*a(n-1) -2*a(n-2). G.f.: (7-5*x) / ((2*x-1)*(x-1)). - R. J. Mathar, May 02 2010
a(n) = 2*A052996(n+1) for n > 0. - Bruno Berselli and Vincenzo Librandi, Aug 27 2010
a(n) = A033484(n+2) - A007283(n). - M. F. Hasler, Dec 11 2018
EXAMPLE
For n = 1, a(1) = 2*(7+1) = 16;
for n = 2, a(2) = 2*(16+1) = 34;
for n = 3, a(3) = 2*(34+1) = 70.
MAPLE
A176449:=n->9*2^n-2; seq(A176449(n), n=0..100); # Wesley Ivan Hurt, Nov 08 2013
MATHEMATICA
Table[9*2^n-2, {n, 0, 100}] (* Wesley Ivan Hurt, Nov 08 2013 *)
LinearRecurrence[{3, -2}, {7, 16}, 40] (* Harvey P. Dale, Jan 12 2024 *)
PROG
(Magma) [9*2^n-2: n in [0..100]]
(PARI) apply( A176449(n)=9<<n-2, [0..99]) \\ M. F. Hasler, Dec 11 2018
CROSSREFS
Sequence in context: A190661 A233058 A301721 * A278945 A327628 A169877
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 18 2010
EXTENSIONS
Edited by M. F. Hasler, Dec 11 2018
STATUS
approved