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Difference of primes pairs alternating between form 4k+3 and 4k+1.
0

%I #5 Mar 30 2012 18:40:01

%S 4,4,4,4,4,8,4,4,4,4,12,4,4,4,8,8,4,8,4,12,12,12,8,8,8,4,4,4,4,4,4,8,

%T 4,12,4,4,8,8,4,4,4,8,4,4,8,4,12,4,8,4,4,24,4,12,12,4,8,4,4,12,4,16,

%U 24,8,4,4,4,4,12,4,12,4,8,16,4,4,8,8,16,4,8,4,8,8,12,4,28,4,12,20,4,12,4,8

%N Difference of primes pairs alternating between form 4k+3 and 4k+1.

%C a(n)>=4 because prime p and prime p + 2 (twin primes) are never at the same time of the form 4k+3 or 4k+1.

%F a(n) = A108811(2n) - A108811(2n-1).

%e a(1)=4 because the difference primes pairs of form 4k+3 11 and 7 = 4;

%e a(2)=4 because the difference primes pairs of form 4k+1 17 and 13 = 4.

%Y Cf. A108811, increasing consecutive prime pairs alternating between form 4k+3 and 4k+1.

%K easy,nonn

%O 1,1

%A _Giovanni Teofilatto_, Jul 15 2005

%E Extended by _Ray Chandler_, Jul 21 2005