OFFSET
0,2
COMMENTS
Partial sums are A097177.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..980
Index entries for linear recurrences with constant coefficients, signature (0,201,0,-10100).
FORMULA
a(n) = (55/sqrt(101))*( (sqrt(101))^n - (-sqrt(101))^n ) + 10^n * (11*(-1)^n-9)/2.
a(n) = 201*a(n-2) - 10100*a(n-4).
MAPLE
seq(coeff(series((1+10*x-101*x^2-900*x^3)/((1-100*x^2)*(1-101*x^2)), x, n+1), x, n), n = 0 ..20); # G. C. Greubel, Sep 17 2019
MATHEMATICA
CoefficientList[Series[(1+10x-101x^2-900x^3)/((1-100x^2)(1-101x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Jan 13 2017 *)
LinearRecurrence[{0, 201, 0, -10100}, {1, 10, 100, 1110}, 20] (* Harvey P. Dale, Mar 03 2018 *)
PROG
(PARI) my(x='x+O('x^20)); Vec((1+10*x-101*x^2-900*x^3)/((1-100*x^2)*(1-101*x^2))) \\ G. C. Greubel, Sep 17 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 20); Coefficients(R!( (1+10*x-101*x^2-900*x^3)/((1-100*x^2)*(1-101*x^2)) )); // G. C. Greubel, Sep 17 2019
(Sage)
def A097178_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P((1+10*x-101*x^2-900*x^3)/((1-100*x^2)*(1-101*x^2))).list()
A097178_list(20) # G. C. Greubel, Sep 17 2019
(GAP) a:=[1, 10, 100, 1110];; for n in [5..20] do a[n]:=201*a[n-2] - 10100*a[n-4]; od; a; # G. C. Greubel, Sep 17 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Jul 30 2004
STATUS
approved