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A140529
a(n) = 6*4^n - 1.
6
5, 23, 95, 383, 1535, 6143, 24575, 98303, 393215, 1572863, 6291455, 25165823, 100663295, 402653183, 1610612735, 6442450943, 25769803775, 103079215103, 412316860415, 1649267441663, 6597069766655, 26388279066623, 105553116266495
OFFSET
0,1
FORMULA
a(n) = 4*a(n-1) + 3, a(0)=5.
a(n) = A002023(n) - 1 = A000302(n+1) + A083420(n).
G.f.: ( 5-2*x ) / ( (4*x-1)*(x-1) ). - R. J. Mathar, Jul 08 2022
MATHEMATICA
NestList[4#+3&, 5, 30] (* Harvey P. Dale, Jan 14 2022 *)
PROG
(Magma) [6*4^n-1: n in [0..30]]; // Vincenzo Librandi, Aug 08 2011
CROSSREFS
Cf. A028894.
Sequence in context: A146013 A028894 A254824 * A055489 A109765 A323922
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Jul 03 2008
STATUS
approved