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%I #22 Sep 02 2019 02:32:28
%S 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,
%T 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,
%U 0,1,0,0,0,1,1,1,1,0,1,1,0,0,1,0,1,0,1,0,1,1,0,1,1,1,0,0,1,0,0,0,0,1,1,1,1
%N For all numbers of the form 6 +- 1 starting with 5,7,11,13,..., '1' indicates prime and '0' indicates composite.
%C The sequence may described as: for all numbers k(n) [k(n) = 6*ceiling(n/2) + (-1)^n] congruent to -1 or +1 (mod 6) starting with k(n) = {5,7,11,13,...}, a(k(n)) is 1 if k(n) is prime and 0 if k(n) is composite. - _Daniel Forgues_, Mar 01 2009
%H Daniel Forgues, <a href="/A075743/b075743.txt">Table of n, a(n) for n = 1..33332</a>
%F a(n) = A010051(A007310(n+2)). - _Reinhard Zumkeller_, Oct 02 2008
%F a(n) = pi(3n+3) - pi(3n), where pi(n) = A000720(n). - _Ridouane Oudra_, Sep 02 2019
%t Boole[PrimeQ/@Flatten[Table[6n+{-1,1},{n,60}]]] (* _Harvey P. Dale_, Jun 04 2017 *)
%Y Cf. A000040, A000720, A007310, A010051.
%Y Absolute value of A156706.
%K easy,nonn
%O 1,1
%A Stephan Wagler (stephanwagler(AT)aol.com), Oct 08 2002
%E Offset corrected by _N. J. A. Sloane_, Feb 02 2009
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