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%I A052187
%S A052187 3,47,199,20183,16763,69593,255767,247099,3565931,6314393,4911251,
%T A052187 12012677,23346737,43607351,34346203,36598517,51041957,460475467,
%U A052187 652576321,742585183,530324329,807620651
%N A052187 Primes p such that p, p+d and p+2d are consecutive primes for some d>
               0.
%C A052187 The first term 3 is anomalous since for all others d is divisible by 
               6. These are minimal terms if in A047948 d=6 is replaced by possible 
               differences: (2), 6, 12, 18, ..., 54, 60.
%F A052187 The least p[k ] such that p[k+1 ]=(p[k ]+p[k+2 ])/2 and p[k+1 ]-p[k ]=d 
               is either 2 or divisible by 6.
%e A052187 a(2)=47 and it is the lower border of a dd pattern: 47[6 ]53[6 ]59. a(10)=6314393 
               and a(10)+54=6314447, a(10)+108=6314501 are consecutive primes and 
               6314393 is the smallest prime prior to a (54,54) difference pattern 
               of A001223.
%t A052187 a = Table[0, {100}]; NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], 
               k++ ]; k]; p = q = r = 0; Do[r = NextPrim[r]; If[r + p == 2q && r 
               - q < 201 && a[[(r - q)/2]] == 0, a[[(r - q)/2]] = p; p = q; q = 
               r, {n, 1, 10^8}]; a
%Y A052187 Cf. A001223, A047948, A052160.
%Y A052187 Cf. A052188-A052189, A052195-A052198.
%Y A052187 Sequence in context: A122535 A058427 A142293 this_sequence A084295 A131465 
               A137611
%Y A052187 Adjacent sequences: A052184 A052185 A052186 this_sequence A052188 A052189 
               A052190
%K A052187 nonn
%O A052187 1,1
%A A052187 Labos E. (labos(AT)ana.sote.hu), Jan 28 2000
%E A052187 More terms from Labos E. (labos(AT)ana.sote.hu), Jan 04 2002
%E A052187 More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 06 2002

    
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Last modified December 4 23:11 EST 2009. Contains 170347 sequences.


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