A103034 - OEIS

This site is supported by donations to The OEIS Foundation.

A103034

Numbers n such that 6*10^n + 4*R_n - 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

1, 2, 7, 19, 25, 37, 49, 133, 613, 1340, 2036, 2491, 26263 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	COMMENTS	`Also numbers n such that (58*10^n-31)/9 is prime.`
	LINKS	`Makoto Kamada, Factorizations of 644...441.` `Index entries for primes involving repunits.`
	MATHEMATICA	`Do[ If[ PrimeQ[(58*10^n - 31)/9], Print[n]], {n, 0, 10000}]`
	CROSSREFS	`Sequence in context: A000988 A002214 A100408 * A038952 A144589 A179002` `Adjacent sequences: A103031 A103032 A103033 * A103035 A103036 A103037`
	KEYWORD	`more,nonn`
	AUTHOR	`Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 18 2005`
	EXTENSIONS	`Addition of a(13) from Kamada data by Robert Price (pamandbobprice(AT)yahoo.com), Dec 13 2010`

Content is available under The OEIS End-User License Agreement .

Last modified February 15 23:53 EST 2012. Contains 205860 sequences.