A139760 First quadrisection of A115451.

1, 9, 137, 2185, 34953, 559241, 8947849, 143165577, 2290649225, 36650387593, 586406201481, 9382499223689, 150119987579017, 2401919801264265, 38430716820228233, 614891469123651721, 9838263505978427529, 157412216095654840457, 2518595457530477447305

Offset: 0

Author

Paul Curtz, May 20 2008

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..500
• Index entries for linear recurrences with constant coefficients, signature (17,-16)

Programs

Magma

[(7+8*16^n)/15: n in [0..20]]; // Vincenzo Librandi, Aug 09 2011

Mathematica

LinearRecurrence[{17,-16},{1,9},20] (* Harvey P. Dale, Apr 02 2018 *)

Formula

a(n) = 16*a(n-1) - 7.

G.f.: ( 1-8*x ) / ( (16*x-1)*(x-1) ). - R. J. Mathar, Feb 06 2011