The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A156706 For all numbers k(n) congruent to +1 or -1 (mod 6) starting with k(n) = {5,7,11,13,...}, a(k(n)) is the congruence (mod 6) if k(n) is prime and 0 if k(n) is composite. 5
 -1, 1, -1, 1, -1, 1, -1, 0, -1, 1, 0, 1, -1, 1, -1, 0, -1, 0, -1, 1, 0, 1, -1, 1, 0, 1, -1, 0, -1, 0, 0, 1, -1, 1, -1, 1, -1, 0, 0, 0, 0, 1, -1, 0, -1, 1, 0, 0, -1, 1, 0, 1, 0, 1, -1, 0, -1, 0, -1, 1, 0, 0, -1, 1, -1, 1, 0, 0, 0, 1, 0, 0, 0, 1, -1, 1, -1, 0, -1, 1, 0, 0, -1, 0, -1, 0, -1, 0, -1, 1, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Expression for k(n): k(n) = 6*ceiling(n/2) + (-1)^n, so the parity of n gives us the congruence (mod 6) of k(n). - Daniel Forgues, Mar 01 2009 LINKS Daniel Forgues, Table of n, a(n) for n = 1..33332 CROSSREFS Cf. A075743. The absolute values of this sequence give A075743. The partial sums of this sequence give A156709. Sequence in context: A341952 A167686 A190207 * A075743 A136705 A141646 Adjacent sequences:  A156703 A156704 A156705 * A156707 A156708 A156709 KEYWORD sign AUTHOR Daniel Forgues, Feb 13 2009, Feb 14 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 17 12:55 EDT 2021. Contains 343971 sequences. (Running on oeis4.)