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%I #11 Nov 21 2019 14:18:23
%S 1327,14563,15683,19609,22307,25471,31397,33647,35617,39251,43801,
%T 44293,49559,69263,69499,76003,79699,81569,82073,85853,88681,88819,
%U 89689,95819,102701,118931,124367,132547,132763,140009,142993,143833
%N Primes for which the six closest primes are smaller.
%H Harvey P. Dale, <a href="/A075038/b075038.txt">Table of n, a(n) for n = 1..2000</a>
%e The six closest primes to 1327 are 1321 (difference = 6), 1319 (difference = 8), 1307 (different = 20), 1303 (difference = 24), 1301 (difference =26) and 1297 (difference = 30). 1321, 1319, 1307, 1303, 1301 and 1297 are all smaller than 1327, so 1327 is in the list.
%t NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; ps = {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, 13872}]
%t Select[Prime[Range[15000]],#-NextPrime[#,-6]<NextPrime[#]-#&] (* _Harvey P. Dale_, Nov 21 2019 *)
%Y Cf. A001223, A074979, A074982, A075030, A075037, A075043, A075050 and A075051.
%K nonn
%O 1,1
%A _Neil Fernandez_, Oct 10 2002
%E Edited by _Robert G. Wilson v_, Oct 11 2002
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