OFFSET
1,3
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..2000
Index entries for linear recurrences with constant coefficients, signature (-1, -1, 1, 1, 1, 1, 1, 1).
FORMULA
G.f.: -((x (1 + x) (1 + x + x^2 + x^4) (1 + x + 2 x^2 + x^3 + x^4 + x^5))/((1 + x + x^2) (-1 + x^3 + x^6))).
MATHEMATICA
Union[# - 1, #, # + 1] &[Fibonacci[Range[50]]]
CoefficientList[Series[-((x (1+x) (1+x+x^2+x^4) (1+x+2 x^2+x^3+x^4+x^5))/((1+x+x^2) (-1+x^3+x^6))), {x, 0, 60}], x] (* or *) LinearRecurrence[{-1, -1, 1, 1, 1, 1, 1, 1}, {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13}, 60] (* Harvey P. Dale, Nov 21 2024 *)
CROSSREFS
KEYWORD
nonn,easy,changed
AUTHOR
Clark Kimberling and Peter J. C. Moses, Jul 01 2015
STATUS
approved