A103047 - OEIS

This site is supported by donations to The OEIS Foundation.

A103047

Numbers n such that 6*10^n + 8*R_n + 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

5, 57, 501, 515, 627, 641, 725, 53111, 65331, 109673 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	COMMENTS	`Also numbers n such that (62*10^n+1)/9 is prime.`
	LINKS	`Makoto Kamada, Factorizations of 688...889.` `Index entries for primes involving repunits.`
	MATHEMATICA	`Do[ If[ PrimeQ[(62*10^n + 1)/9], Print[n]], {n, 0, 10000}]`
	CROSSREFS	`Sequence in context: A000362 A196971 A197558 * A107339 A139260 A114466` `Adjacent sequences: A103044 A103045 A103046 * A103048 A103049 A103050`
	KEYWORD	`more,nonn`
	AUTHOR	`Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 18 2005`
	EXTENSIONS	`a(8)-a(10) from Kamada data by Robert Price (pamandbobprice(AT)yahoo.com), Dec 14 2010`

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

Last modified February 16 20:10 EST 2012. Contains 205960 sequences.