OFFSET
1,3
COMMENTS
Used to illustrate Besicovitch's density theorem.
REFERENCES
H. Halberstam and K. F. Roth, Sequences, Oxford, 1966; see p. 6.
LINKS
FORMULA
G.f.: x^2*(1+7*x-7*x^2)/(1-x)^2. - Bruno Berselli, Sep 02 2011
MATHEMATICA
Complement[Range[0, 100], Range[2, 8]] (* Harvey P. Dale, Oct 10 2014 *)
PROG
(PARI) a(n)=if(n>2, n+6, n-1) \\ Charles R Greathouse IV, Sep 02 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Oct 19 2010
STATUS
approved