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Differences of two consecutive primes which both equal 1 modulo 3, divided by 6.
3

%I #10 Jun 26 2022 05:10:03

%S 1,1,1,1,1,2,2,1,1,1,1,1,3,1,1,1,1,2,2,1,1,1,1,2,1,1,3,1,1,2,1,2,1,1,

%T 3,1,2,2,1,1,1,4,1,1,1,3,1,2,1,1,1,1,3,4,1,1,1,1,1,1,3,1,1,1,1,1,1,2,

%U 1,2,2,1,2,1,1,1,2,2,1,1,2,1,1,1,1,1

%N Differences of two consecutive primes which both equal 1 modulo 3, divided by 6.

%C a(n) = (A217659(n) - A185934(n)) / 6.

%H Reinhard Zumkeller, <a href="/A219244/b219244.txt">Table of n, a(n) for n = 1..1000</a>

%t (Last[#]-First[#])/6&/@Select[Partition[Prime[Range[800]],2,1], Mod[First[#],3] == Mod[Last[#],3]==1&] (* _Harvey P. Dale_, Feb 26 2013 *)

%o (Haskell)

%o a219244 n = a219244_list !! (n-1)

%o a219244_list = map (`div` 6) $ zipWith (-) a217659_list a185934_list

%Y Cf. A185934, A217659.

%K nonn

%O 1,6

%A _Reinhard Zumkeller_, Nov 16 2012