OFFSET
0,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (1, -2, 2, 2, 1, 1).
FORMULA
a(n)=a(n-1)-2a(n-2)+2a(n-3)+2a(n-4)+a(n-5)+a(n-6).
G.f.: (6-5x+8x^2-6x^3-4x^4-x^5)/(1-x+2x^2-2x^3-2x^4-x^5-x^6).
abs(a(n)) = abs(A074193(n)). - Joerg Arndt, Oct 22 2020
MATHEMATICA
CoefficientList[Series[(6-5*x+8*x^2-6*x^3-4*x^4-x^5)/(1-x+2*x^2-2*x^3-2*x^4-x^5-x^6), {x, 0, 40}], x]
LinearRecurrence[{1, -2, 2, 2, 1, 1}, {6, 1, -3, 1, 17, 16}, 50] (* Harvey P. Dale, Mar 16 2012 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Mario Catalani (mario.catalani(AT)unito.it), Aug 22 2002
STATUS
approved