A103099 - OEIS

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A103099

Numbers n such that 9*10^n + 4*R_n + 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

1, 2, 4, 25, 58, 148, 373, 421, 1915, 3746, 16784 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	COMMENTS	`Also numbers n such that (85*10^n+23)/9 is prime.`
	LINKS	`Makoto Kamada, Factorizations of 944...447.` `Index entries for primes involving repunits.`
	MATHEMATICA	`Do[ If[ PrimeQ[(85*10^n + 23)/9], Print[n]], {n, 0, 10000}]`
	CROSSREFS	`Sequence in context: A128299 A143672 A001510 * A119029 A162120 A162121` `Adjacent sequences: A103096 A103097 A103098 * A103100 A103101 A103102`
	KEYWORD	`more,nonn`
	AUTHOR	`Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 19 2005`
	EXTENSIONS	`a(11) from Kamada data by Robert Price (pamandbobprice(AT)yahoo.com), Dec 14 2010`

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Last modified February 14 08:49 EST 2012. Contains 205614 sequences.