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%I #6 Oct 07 2011 16:48:57
%S 1,1,1,2,1,2,2,1,2,4,1,1,2,3,1,2,1,3,4,3,5,2,1,1,5,4,4,3,5,2,3,2,1,6,
%T 5,1,2,3,7,5,5,7,2,10,5,8,1,2,5,2,1,1,2,7,1,2,9,4,4,7,6,6,3,5,6,3,1,7,
%U 5,1,5,6,5,4,3,2,5,2,2,4,3,4,3,14,3,4,4,2,9,2,7,9,8,7,4,13
%N Let q(n) be the prime defined in A078497; sequence gives (q(n)-prime(n))/6.
%F For n>4 a(n)=( min{p : p>prime(n), p and 2*prime(n)-p are primes} - prime(n) ) / 6.
%e a(6)=1, a(25)=5.
%t Table[p = Prime[i]; j = 0; While[j++; df = 6*j; ! ((PrimeQ[p + df]) && (PrimeQ[p - df]))]; j, {i, 5, 100}]
%Y Cf. A078496, A078497.
%K nonn,easy
%O 5,4
%A Serhat Sevki Dincer (sevki(AT)ug.bilkent.edu.tr), Nov 27 2002
%E More terms from Pab Ter (pabrlos(AT)yahoo.com), May 27 2004