OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (35,-449,2485,-4950).
FORMULA
a(n) = 21*a(n-1) - 110*a(n-2) + (9^(n+1) - 5^(n+1))/4, n>=2. - Vincenzo Librandi, Mar 12 2011
a(n) = -5^(n+2)/24 +11^(n+3)/12 -2*10^(n+2) +3^(2*n+6)/8. - R. J. Mathar, Mar 14 2011
MATHEMATICA
CoefficientList[ Series[1/(1 - 35x + 449x^2 - 2485x^3 + 4950x^4), {x, 0, 15}], x] (* Or *)
a[n_] := 21 a[n - 1] - 110 a[n - 2] + (9^(n + 1) - 5^(n + 1))/4; a[0] = 1; a[1] = 35; Array[a, 16, 0] (* Robert G. Wilson v, Mar 14 2011 *)
LinearRecurrence[{35, -449, 2485, -4950}, {1, 35, 776, 13930}, 20] (* Harvey P. Dale, Feb 24 2014 *)
PROG
(Magma) I:=[1, 35, 776, 13930]; [n le 4 select I[n] else 35*Self(n-1)-449*Self(n-2)+2485*Self(n-3)-4950*Self(n-4): n in [1..20]]; // Vincenzo Librandi, Feb 26 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Vincenzo Librandi, Feb 26 2014
STATUS
approved