OFFSET
0,2
COMMENTS
Row sums of triangle in A018900 (without the initial 0). - Reinhard Zumkeller, Jun 24 2009
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..3000 (corrected by Ray Chandler, Jan 19 2019)
Index entries for linear recurrences with constant coefficients, signature (5,-8,4).
FORMULA
a(n) = (n + 1) * 2^n - 1 = 2^n * n + 2^n - 1.
a(n) = 5*a(n-1) - 8*a(n-2) + 4*a(n-3). G.f.: x*(3-4*x)/((1-x)*(1-2*x)^2). - Colin Barker, Mar 23 2012
a(n) = A001787(n+1) - 1. - Omar E. Pol, Nov 09 2013
MATHEMATICA
Table[(n + 1)2^n - 1, {n, 0, 29}] (* Alonso del Arte, Jan 31 2014 *)
LinearRecurrence[{5, -8, 4}, {0, 3, 11}, 40] (* Harvey P. Dale, Sep 15 2019 *)
PROG
(Magma) [((n+1)*2^n - 1): n in [1..30]]; // Vincenzo Librandi, Sep 29 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Sep 03 2003
EXTENSIONS
Edited and extended by David Wasserman, May 06 2005
Formula promoted to definition and offset adjusted to 0 by Alonso del Arte, Jan 31 2014
STATUS
approved