A102937 - OEIS

This site is supported by donations to The OEIS Foundation.

A102937

Numbers n such that 10^n + 5*R_n + 2 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

0, 1, 2, 5, 7, 19, 20, 28, 58, 250, 397, 7591 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,3`
	COMMENTS	`Also numbers n such that (14*10^n+13)/9 is prime.`
	LINKS	`Makoto Kamada, Factorizations of 155...557.` `Index entries for primes involving repunits.`
	MATHEMATICA	`Do[ If[ PrimeQ[(14*10^n + 13)/9], Print[n]], {n, 0, 10000}]`
	CROSSREFS	`Sequence in context: A173929 A173299 A097052 * A045358 A128005 A045359` `Adjacent sequences: A102934 A102935 A102936 * A102938 A102939 A102940`
	KEYWORD	`more,nonn`
	AUTHOR	`Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 16 2004`
	EXTENSIONS	`0 added by Arkadiusz Wesolowski (wesolowski(AT)aol.pl), Mar 10 2011`

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

Last modified February 17 03:45 EST 2012. Contains 205978 sequences.