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%I #18 Oct 09 2023 13:44:32
%S 7,59,163,179,223,263,269,379,569,599,613,659,739,953,983,1109,1129,
%T 1193,1229,1373,1523,1753,1759,1913,2293,2423,2683,2909,2969,3313,
%U 3319,3643,3739,4019,4421,4463,4603,4663,4703,4999,5113,5119,5309,5393,5399
%N Primes p such that p and the two previous primes are in arithmetic progression.
%C Call d(i)=p(i+2)-p(i+1) and dd(i)=d(i+1)-d(i) then dd(i)=0.
%C All related first differences are multiples of 6 except the first one, which is 2.
%H Reinhard Zumkeller, <a href="/A181424/b181424.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000040(A064113(n) + 2). - _Reinhard Zumkeller_, Jan 20 2012
%e a(7)=269 since d(269,263)=6 and d(263,257)=6 and their difference is 0.
%t Select[Partition[Prime[Range[750]],3,1],Length[Union[Differences[#]]]==1&][[;;,3]] (* _Harvey P. Dale_, Oct 09 2023 *)
%o (Haskell)
%o a181424 = a000040 . (+ 2) . a064113 -- _Reinhard Zumkeller_, Jan 20 2012
%Y Cf. A000045, A054643, A122535, A006562.
%K nonn
%O 1,1
%A _Carmine Suriano_, Oct 18 2010
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