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%I #7 Jun 03 2013 03:35:54
%S 1,2,1,1,0,1,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,0,1,1,0,0,1,
%T 0,1,1,0,0,1,0,1,0,0,1,0,0,0,1,0,1,1,0,1,1,0,1,0,0,0,0,0,0,1,0,1,0,0,
%U 1,1,0,0,0,0,1,1,0,0,1,0,0,1,0,1,0,0,1,0,0,1,1,0,0,0,0,1,1,0,1,1,0,0,0,0,0
%N Number of primes between two consecutive even numbers.
%F a(n)=A101264(n), n>1. [From _R. J. Mathar_, Dec 13 2008]
%e a(1)=2 because between 2 and 4 there are two primes: 2,3;
%e a(2)=1 because between 4 and 6 there is one prime: 5;
%e a(4)=0 because between 8 and 10 there are no primes.
%o (PARI) a(n) = if (n==0, 1, if (n==1, 2, isprime(2*n+1))) \\ _Michel Marcus_, Jun 03 2013
%K easy,nonn
%O 0,2
%A _Giovanni Teofilatto_, Jan 27 2005
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