OFFSET
0,3
COMMENTS
Partial sums of A046173. [Joerg Arndt, Jun 10 2013]
LINKS
FORMULA
a(n) = ((49+20*sqrt(6))^n+(49-20*sqrt(6))^n -2)/96 = 98*a(n-1)-a(n-2)+2 = 99*a(n-1)-99*a(n-2)+a(n-3) = (a(n-1)-1)^2/a(n-2) = A004189(n)^2.
G.f.: -x*(x+1)/((x-1)*(x^2-98*x+1)). [Colin Barker, Oct 24 2012]
From Wolfdieter Lang, Feb 01 2016: (Start)
a(n) = (T(n, 49) - 1)/48 = (T(2*n, 5) - 1)/48 with Chebyshev's T polynomials A053120. See the name.
a(n) = A000217((T(n, 5) - 1)/2)/3. n >= 0.
MATHEMATICA
LinearRecurrence[{99, -99, 1}, {0, 1, 100}, 20] (* Vincenzo Librandi, Feb 02 2016 *)
PROG
(Magma) I:=[0, 1, 100]; [n le 3 select I[n] else 99*Self(n-1)-99*Self(n-2)+Self(n-3): n in [1..20]]; // Vincenzo Librandi, Feb 02 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Henry Bottomley, Jun 22 2005
STATUS
approved