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%I #13 Mar 25 2013 11:24:05
%S 15683,25471,31397,43801,44293,69499,89689,102701,124367,142993,
%T 155921,162293,166871,172441,183527,193891,196201,198859,203461,
%U 206827,212701,221101,225167,225383,248909,256219,259033,265621,282713,288583,290249
%N Primes for which the seven closest primes are smaller.
%C If 9 consecutive primes are p1, p2, p3 ... p9, p8 is included in the sequence if p8-p1 is less than p9-p8. - _Harvey P. Dale_, Mar 25 2013
%H Harvey P. Dale, <a href="/A075043/b075043.txt">Table of n, a(n) for n = 1..1000</a>
%e The seven closest primes to 15683 are 15679 (difference = 4), 15671 (difference = 12), 15667 (difference = 16), 15661 (difference = 22), 15649 (difference = 34) and 15647 (difference = 36). These are all smaller than 15683 so 15683 is in the list.
%t NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; ps = {0, 0, 0, 0, 0, 0, 0, 0, 1}; Do[ps = Drop[ps, 1]; ps = Append[ps, NextPrim[ ps[[ -1]]]]; If[ ps[[ -1]] - ps[[ -2]] > ps[[ -2]] - ps[[1]], Print[ ps[[ -2]]]], {n, 1, 26185}]
%t Transpose[Select[Partition[Prime[Range[25000]],9,1],#[[8]]-#[[1]]<#[[9]]- #[[8]]&]][[8]](* _Harvey P. Dale_, Mar 25 2013 *)
%Y Cf. A001223, A074979, A074982, A075030, A075037, A075038, A075050 and A075051.
%K nonn
%O 1,1
%A _Neil Fernandez_, Oct 10 2002
%E Edited and extended by _Robert G. Wilson v_, Oct 11 2002
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