OFFSET
0,1
COMMENTS
a(n)^4 = Sum_{j=0..(16*n*(17*n+14)+46)} (-1)^j*(119*n^2 + 98*n + 20 + j)^2. - Bruno Berselli, Apr 30 2010
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
G.f.: (7+10*x)/(1-x)^2. - Colin Barker, Jan 09 2012
a(n) = 2*a(n-1) - a(n-2). - Vincenzo Librandi, Feb 26 2012
E.g.f.: (7 + 17*x)*exp(x). - G. C. Greubel, May 31 2024
EXAMPLE
For n=5, a(5)^4 = 92^4 = 71639296 = 3485^2-3486^2+3487^2-..+11449^2-11450^2+11451^2. - Bruno Berselli, Apr 30 2010
MATHEMATICA
Range[7, 1000, 17] (* Vladimir Joseph Stephan Orlovsky, Jun 01 2011 *)
PROG
(Magma) I:=[7, 24]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]]; // Vincenzo Librandi, Feb 21 2012
(PARI) for(n=0, 50, print1(17*n + 7", ")); \\ Vincenzo Librandi, Feb 26 2012
(SageMath) [17*n+7 for n in range(61)] # G. C. Greubel, May 31 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 15 2009
EXTENSIONS
Offset corrected by Bruno Berselli, Aug 16 2010
STATUS
approved