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A181424
Primes p such that p and the two previous primes are in arithmetic progression.
11
7, 59, 163, 179, 223, 263, 269, 379, 569, 599, 613, 659, 739, 953, 983, 1109, 1129, 1193, 1229, 1373, 1523, 1753, 1759, 1913, 2293, 2423, 2683, 2909, 2969, 3313, 3319, 3643, 3739, 4019, 4421, 4463, 4603, 4663, 4703, 4999, 5113, 5119, 5309, 5393, 5399
OFFSET
1,1
COMMENTS
Call d(i)=p(i+2)-p(i+1) and dd(i)=d(i+1)-d(i) then dd(i)=0.
All related first differences are multiples of 6 except the first one, which is 2.
LINKS
FORMULA
a(n) = A000040(A064113(n) + 2). - Reinhard Zumkeller, Jan 20 2012
EXAMPLE
a(7)=269 since d(269,263)=6 and d(263,257)=6 and their difference is 0.
MATHEMATICA
Select[Partition[Prime[Range[750]], 3, 1], Length[Union[Differences[#]]]==1&][[;; , 3]] (* Harvey P. Dale, Oct 09 2023 *)
PROG
(Haskell)
a181424 = a000040 . (+ 2) . a064113 -- Reinhard Zumkeller, Jan 20 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Carmine Suriano, Oct 18 2010
STATUS
approved