A199209 a(n) = 10*4^n+1.

11, 41, 161, 641, 2561, 10241, 40961, 163841, 655361, 2621441, 10485761, 41943041, 167772161, 671088641, 2684354561, 10737418241, 42949672961, 171798691841, 687194767361, 2748779069441, 10995116277761, 43980465111041

Offset: 0

Author

Vincenzo Librandi, Nov 04 2011

Keywords

• nonn
• easy

Comments

Bisection (odd part) of A083575. - Bruno Berselli, Nov 04 2011

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (5,-4).

Crossrefs

Cf. A083575.

Programs

Magma

[10*4^n+1: n in [0..30]];

Mathematica

10*4^Range[0,30]+1 (* or *) LinearRecurrence[{5,-4},{11,41},30] (* Harvey P. Dale, May 27 2019 *)

Formula

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

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

G.f.: (11-14*x)/((1-x)*(1-4*x)). - Bruno Berselli, Nov 04 2011