OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
FORMULA
a(n) = n*(43*n-41)/2.
G.f.: x*(1+42*x)/(1-x)^3. - Bruno Berselli, Feb 04 2011
a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). - Vincenzo Librandi, Jul 08 2012
E.g.f.: exp(x)*(x + 43*x^2/2). - Nikolaos Pantelidis, Feb 10 2023
MATHEMATICA
Table[n(43n - 41)/2, {n, 1, 40}] (* Stefan Steinerberger, Feb 15 2006 *)
CoefficientList[Series[(1+42*x)/(1-x)^3, {x, 0, 50}], x] (* Vincenzo Librandi, Jul 08 2012 *)
LinearRecurrence[{3, -3, 1}, {1, 45, 132}, 40] (* Harvey P. Dale, Jan 24 2015 *)
PROG
(Magma)[n*(43*n-41)/2: n in [1..50]]; // Vincenzo Librandi, Jul 08 2012
(PARI) a(n)=n*(43*n-41)/2 \\ Charles R Greathouse IV, Oct 16 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Oct 18 2004
EXTENSIONS
More terms from Stefan Steinerberger, Feb 15 2006
STATUS
approved