OFFSET
0,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,-2).
FORMULA
a(n+1) = 2*a(n) + 1.
G.f.: ( 18-17*x ) / ( (2*x-1)*(x-1) ). - R. J. Mathar, Oct 25 2011
a(n) + a(n-1)^2 = (a(n-1)+1)^2. - Vincenzo Librandi, Jun 11 2014
EXAMPLE
a(2) = 19*2^2-1 = 75.
MAPLE
MATHEMATICA
19*2^Range[0, 30]-1 (* or *) LinearRecurrence[{3, -2}, {18, 37}, 40] (* Harvey P. Dale, Dec 18 2013 *)
PROG
(BASIC) for j = 0 to 30 : print str$((19*2^j)-1)+", "; : next j
(Magma) [19*2^n-1: n in [0..30]]; // Vincenzo Librandi, Oct 28 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jeremy Gardiner, Oct 23 2011
STATUS
approved