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%I #48 Feb 25 2017 14:06:31
%S 3,3,17,41,47,67,151,167,199,227,251,257,347,367,557,587,601,607,641,
%T 647,727,941,971,1051,1091,1097,1117,1181,1217,1277,1361,1427,1447,
%U 1447,1487,1487,1499,1607,1697,1741,1747,1741,1777,1877,1901,2087,2143,2281
%N Primes of the form 2*prime(k) - prime(k+1).
%C Corresponding values of k: 3, 4, 9, 15, 16, 21, 37, 40, 47, 51, 55, 56, 71, 74, 103 (A216075).
%H Zak Seidov, <a href="/A215808/b215808.txt">Table of n, a(n) for n = 1..1000</a>
%e k=3: 2*5-7=3, k=4: 2*7-11=3, k=9: 2*23-29=17.
%t pr=Prime[Range[1000]]; s=Select[2*Most[pr]-Rest[pr],PrimeQ]
%t Select[2#[[1]]-#[[2]]&/@Partition[Prime[Range[500]],2,1],PrimeQ] (* _Harvey P. Dale_, Feb 25 2017 *)
%Y Cf. A062234, A085704, A094104, A094105, A216075.
%K nonn
%O 1,1
%A _Zak Seidov_, Sep 06 2012
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