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A064218 Least k such that k*10^n +/- 1 are twin primes. 0
4, 3, 6, 3, 18, 240, 24, 3, 174, 93, 57, 141, 465, 501, 105, 822, 552, 324, 555, 237, 867, 1488, 543, 2556, 1050, 105, 51, 429, 1470, 147, 567, 1329, 636, 5016, 645, 4713, 1116, 1029, 462, 567, 5757, 951, 5547, 1245, 2823, 5931, 1989, 525, 6246, 1716 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..50.

MATHEMATICA

Do[ k = 1; While[ ! PrimeQ[ k*10^n + 1 ] || ! PrimeQ[ k*10^n - 1 ], k++ ]; Print[ k ], {n, 0, 50} ]

CROSSREFS

Cf. A063983.

Sequence in context: A317698 A179103 A045814 * A228780 A109339 A071989

Adjacent sequences:  A064215 A064216 A064217 * A064219 A064220 A064221

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Sep 21 2001

STATUS

approved

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Last modified November 20 14:54 EST 2019. Contains 329337 sequences. (Running on oeis4.)