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%I #7 Oct 04 2017 14:03:27
%S 0,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,
%T 0,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,
%U 0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,0
%N The characteristic function of primes > 3: 1 if n is prime such that neither prime+-1 is prime else 0.
%H Antti Karttunen, <a href="/A171387/b171387.txt">Table of n, a(n) for n = 1..1001</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F A010051(n) = a(n) + A171386(n).
%F If n > 3, a(n) = A010051(n), otherwise a(n) = 0. - _Antti Karttunen_, Oct 04 2017
%Y Cf. A000007, A010051, A063524, A080545, A169546, A171386.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Dec 07 2009