OFFSET
0,2
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..250
Index entries for linear recurrences with constant coefficients, signature (0,5,0,-4).
FORMULA
a(n) = A059222(n+1) if n <> 1.
From Colin Barker, Mar 19 2014: (Start)
G.f.: (4*x^5-9*x^3-x^2+2*x+1) / ((x-1)*(x+1)*(2*x-1)*(2*x+1)).
a(n) = 5*a(n-2)-4*a(n-4) for n>5.
a(n) = (1+(-2)^n-(-1)^n+2^n)/2 for n>1. (End).
EXAMPLE
a(0) = 1-1, a(1) = 0+1/2, a(2) = -1/12-1/6=-1/4.
MAPLE
A224783 := proc(n)
bernoulli(n, 1/2)-bernoulli(n) ;
denom(%) ;
end proc: # R. J. Mathar, Apr 25 2013
MATHEMATICA
Table[Denominator[BernoulliB[n, 1/2] - BernoulliB[n, 0]], {n, 0, 50}] (* Vincenzo Librandi, Mar 19 2014 *)
PROG
(PARI) Vec((4*x^5-9*x^3-x^2+2*x+1)/((x-1)*(x+1)*(2*x-1)*(2*x+1)) + O(x^100)) \\ Colin Barker, Mar 20 2014
CROSSREFS
KEYWORD
nonn,frac,less,easy
AUTHOR
Paul Curtz, Apr 17 2013
STATUS
approved