A199116 a(n) = 6*4^n+1.

7, 25, 97, 385, 1537, 6145, 24577, 98305, 393217, 1572865, 6291457, 25165825, 100663297, 402653185, 1610612737, 6442450945, 25769803777, 103079215105, 412316860417, 1649267441665, 6597069766657, 26388279066625, 105553116266497

Offset

0,1

Comments

Bisection (odd part) of A181565 and A201630. - Bruno Berselli, Dec 04 2011

First differences of A221130, a(n) = A221130(n+2) - A221130(n+1). - Jaroslav Krizek, Jan 02 2013

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (5,-4).

Formula

a(n) = 4*a(n-1)-3.

a(n) = 5*a(n-1)-4*a(n-2).

G.f.: (7-10*x)/((1-x)*(1-4*x)). - Bruno Berselli, Nov 04 2011

Mathematica

6*4^Range[0, 30]+1 (* or *) LinearRecurrence[{5, -4}, {7, 25}, 30] (* Harvey P. Dale, Apr 18 2024 *)

Prog

(Magma) [6*4^n+1: n in [0..30]];

Crossrefs

Cf. A181565, A201630, A221130.

Sequence in context: A155258 A261722 A256370 * A304421 A138729 A035509

Adjacent sequences: A199113 A199114 A199115 * A199117 A199118 A199119

Keyword

nonn,easy,changed

Author

Vincenzo Librandi, Nov 04 2011

Status

approved