%I #16 Apr 29 2019 03:18:33
%S 47,23,73,61,353,31,233,131,331,653,2441,3733,1033,4871,1063,1621,503,
%T 607,4211,7823,2287,83,383,1231,2903,5981,1123,173,11981,11833,1367,
%U 2063,4723,19681,2207,2131,2713,9533,6571,1657,23081,15913,7013,14051
%N First primes of A031924 (lesser of 6-twins) with increasing distance to the next 6-twin.
%C The increment of distance of 6-twins (A053321) is 2 (not 6), the smallest distance (A052380) is 6.
%C The middle gap 2n-2 may include primes, e.g., n=10, a(10)=653 and between 659 and 659 + 2*10 - 2 = 677, two primes occur.
%F a(n) = p yields a prime quadruple [p, p+6, p+2n+4, p+2n+4+6] with difference pattern [6, 2n-2, 6].
%e For n=1,2,3 the quadruples are [47,53,53,59] (a triple), [23,29,31,37], [73,79,83,89] with 53 - 47 = 6, 31 - 23 = 8 and 83 - 73 = 10 twin distances.
%Y Cf. A031924, A053321, A052380, A052381.
%K nonn
%O 1,1
%A _Labos Elemer_, Mar 07 2000
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