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%I #20 Oct 21 2014 03:08:32
%S 7,71,71428571,7142857142857,7142857142857142857142857142857
%N Primes formed by the initial digits of the decimal expansion of 1/14, starting at the first nonzero digit in the expansion.
%C a(6) has 104 digits. - _Michel Marcus_, May 26 2014
%o (PARI) lista(nn) = {v = [7,1,4,2,8,5]; n = 0; for (i=0, nn, n = 10*n+ v[(i % 6)+1]; if (ispseudoprime(n), print1(n, ", ")););} \\ _Michel Marcus_, May 26 2014
%Y Cf. A021018.
%Y Corresponding sequences for 1/k: A242824 (k=7), A093676 (k=12), A242826 (k=13), A242828 (k=17), A242833 (k=19).
%K nonn,base
%O 1,1
%A _Felix Fröhlich_, May 23 2014