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A242827
Primes formed by the initial digits of the decimal expansion of 1/14, starting at the first nonzero digit in the expansion.
4
7, 71, 71428571, 7142857142857, 7142857142857142857142857142857
OFFSET
1,1
COMMENTS
a(6) has 104 digits. - Michel Marcus, May 26 2014
PROG
(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
CROSSREFS
Cf. A021018.
Corresponding sequences for 1/k: A242824 (k=7), A093676 (k=12), A242826 (k=13), A242828 (k=17), A242833 (k=19).
Sequence in context: A022503 A063861 A093632 * A077332 A222833 A005413
KEYWORD
nonn,base
AUTHOR
Felix Fröhlich, May 23 2014
STATUS
approved