login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A097325 Periodic sequence 0,1,1,1,1,1... 13
0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

a(n) is 0 if 6 divides n, 1 otherwise.

Contribution from Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 30 2009: (Start)

a(n)=1-A079979(n); a(A047253(n))=1; a(A008588(n))=0;

A033438(n) = SUM(a(k)*(n-k): 0<=k<=n). (End)

LINKS

Index entries for characteristic functions [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 30 2009]

FORMULA

G.f.: 1/(1-x) - 1/(1-x^6) = Sum[k>=0, x^k - x^(6k)].

Recurrence: a(n+6) = a(n), a(0) = 0, a(i) = 1, 1 <= i <= 5.

a(n) = (1/4) * {3 - (-1)^n - (-1)^[(n+1)/3] - (-1)^[(2n+1)/3]}.

a(n)={[(1/3)*(cos(2*n*Pi/3)+1/2)*(1+(-1)^n)]-1}^2 - Paolo P. Lava (paoloplava(AT)gmail.com), Oct 09 2006

Dirichlet g.f. (1-1/6^s)*zeta(s). - R. J. Mathar, Feb 19 2011

PROG

(PARI) a(n) = sign(n%6)

CROSSREFS

Characteristic sequence of A047253. Binary complement of A079979.

Cf. A168185, A145568, A168184, A168182, A168181, A109720, A011558, A166486, A011655, A000035. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 30 2009]

Sequence in context: A143536 A080110 A122895 * A167393 A106549 A075897

Adjacent sequences:  A097322 A097323 A097324 * A097326 A097327 A097328

KEYWORD

nonn,easy

AUTHOR

Ralf Stephan, Aug 16 2004

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 15 07:16 EST 2012. Contains 205700 sequences.