OFFSET
0,3
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).
FORMULA
G.f.: 60*x^2*(1 +5*x +5*x^2 +x^3)/(1-x)^7. - Alexander R. Povolotsky, Apr 01 2008
From Amiram Eldar, Jan 12 2021: (Start)
Sum_{n>=2} 1/a(n) = 7/8 - Pi^2/6 + Pi*coth(Pi)/4.
a(n) = 7*a(n-1) -21*a(n-2) +35*a(n-3) -35*a(n-4) +21*a(n-5) -7*a(n-6) +a(n-7). - Wesley Ivan Hurt, May 04 2021
From G. C. Greubel, Feb 07 2022: (Start)
a(n) = 6*binomial(n^2 + 1, 3).
E.g.f.: x^2*(30 +90*x +65*x^2 +15*x^3 +x^4)*exp(x). (End)
MATHEMATICA
f[n_]:=n^6-n^2; f[Range[0, 60]] (* Vladimir Joseph Stephan Orlovsky, Feb 10 2011 *)
PROG
(Sage) [n^2*(n^4-1) for n in range(0, 31)] # Zerinvary Lajos, Jul 16 2008
(Magma) [6*Binomial(n^2 +1, 3): n in [0..30]]; // G. C. Greubel, Feb 07 2022
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Rolf Pleisch, Mar 16 2008
EXTENSIONS
Extended by Ray Chandler, Dec 13 2008
STATUS
approved