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A093673 Primes of the form 4*10^n + 3*R_n, where R_n is the repunit (A002275) of length n. 2
43, 433, 43333333333333333, 43333333333333333333333333333333, 43333333333333333333333333333333333333, 43333333333333333333333333333333333333333333333333333333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..6.

Makoto Kamada, Prime numbers of the form 433...33.

Index entries for primes involving repunits

CROSSREFS

Cf. A002275, A056707 (corresponding n).

Sequence in context: A142913 A228908 A027002 * A244769 A239268 A247966

Adjacent sequences:  A093670 A093671 A093672 * A093674 A093675 A093676

KEYWORD

nonn

AUTHOR

Rick L. Shepherd, Apr 08 2004

STATUS

approved

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Last modified December 12 10:19 EST 2019. Contains 329953 sequences. (Running on oeis4.)