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Average of twin-prime pairs modulo 10 (least absolute residue).
0

%I #6 Oct 12 2013 15:24:51

%S 4,-4,2,-2,0,2,0,2,2,-2,-2,0,0,2,-2,-2,0,0,2,2,-2,0,2,2,2,0,0,-2,2,0,

%T 0,2,-2,-2,2,0,2,0,2,2,2,0,-2,0,2,0,-2,2,2,-2,-2,0,-2,-2,2,-2,2,-2,2,

%U 0,-2,-2,2,-2,2,0,2,-2,-2,0,0,2,0,2,-2,-2,2,0,0,2,0,0,0,-2,2,-2,0,0,0,2,0,2,-2,-2,0,-2,2,2,-2,2,2,-2,0,2,0,0,2,-2,-2,-2,0

%N Average of twin-prime pairs modulo 10 (least absolute residue).

%C All terms after a(2) are 0, 2, or -2. - _Franklin T. Adams-Watters_, Aug 27 2012

%e First twin-prime average = (3+5)/2 = 4: a(1) = +4.

%e Second twin-prime average = (5+7)/2 = 6 (= -4+1*10): a(2) = -4.

%e Third twin-prime average = (11+13)/2 = 12 (= 2+1*10): a(3) = +2.

%Y Cf. A014574.

%K sign

%O 1,1

%A _Greg Huber_, Jul 18 2006

%E Edited by _Franklin T. Adams-Watters_, Aug 27 2012