A103108 - OEIS

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A103108

Numbers n such that 9*10^n + 8*R_n - 5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

2, 3, 32, 42, 75, 368, 1392, 16350 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	COMMENTS	`Also numbers n such that (89*10^n-53)/9 is prime.`
	LINKS	`Makoto Kamada, Factorizations of 988...883.` `Index entries for primes involving repunits.`
	MATHEMATICA	`Do[ If[ PrimeQ[(89*10^n - 53)/9], Print[n]], {n, 0, 10000}]`
	CROSSREFS	`Sequence in context: A032815 A176894 A041053 * A107124 A141049 A052830` `Adjacent sequences: A103105 A103106 A103107 * A103109 A103110 A103111`
	KEYWORD	`more,nonn`
	AUTHOR	`Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 19 2005`
	EXTENSIONS	`a(8) from Kamada data by Robert Price (pamandbobprice(AT)yahoo.com), Dec 14 2010`

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Last modified February 17 16:13 EST 2012. Contains 206050 sequences.