OFFSET
0,3
COMMENTS
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,-2,0,-1,3,-2).
FORMULA
a(n) + a(n+4) = 2^(n+4) - 1.
From Joerg Arndt, Apr 09 2013: (Start)
G.f.: x/((1-x)*(1-2*x)*(1+x^4)).
a(n) = +3*a(n-1) -2*a(n-2) -1*a(n-4) +3*a(n-5) -2*a(n-6). (End)
a(n) = floor(2^(n+4)/17). - Karl V. Keller, Jr., Jun 30 2021
MATHEMATICA
CoefficientList[Series[x/((1 - x)*(1 - 2*x)*(1 + x^4)), {x, 0, 50}], x] (* G. C. Greubel, Oct 11 2017 *)
LinearRecurrence[{3, -2, 0, -1, 3, -2}, {0, 1, 3, 7, 15, 30}, 40] (* Harvey P. Dale, Aug 23 2021 *)
PROG
(PARI) x='x+O('x^50); concat([0], Vec(x/((1-x)*(1-2*x)*(1+x^4)))) \\ G. C. Greubel, Oct 11 2017
(Python) print([2**(n+4)//17 for n in range(31)]) # Karl V. Keller, Jr., Jun 30 2021
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Arie Bos, Apr 09 2013
STATUS
approved