A140293 - OEIS

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A140293

Numbers n such that n!/n#-1 is prime.

4, 5, 6, 7, 8, 16, 17, 21, 34, 39, 45, 50, 72, 73, 76, 133, 164 (list; graph; refs; listen; history; internal format)

	OFFSET	`4,1`
	FORMULA	`n# is the primorial function.`
	EXAMPLE	`7!/7# = 24. 24-1=23,prime.`
	PROG	`(PARI) g(n) = for(x=4, n, y=x!/primorial(x)-1; z=nextprime(y+1); if(ispseudoprime(y), print1(x", ")))`
	CROSSREFS	`Sequence in context: A050038 A059709 A071623 * A075341 A143789 A068521` `Adjacent sequences: A140290 A140291 A140292 * A140294 A140295 A140296`
	KEYWORD	`nonn`
	AUTHOR	`Cino Hilliard (hillcino368(AT)hotmail.com), May 25 2008`

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Last modified February 17 09:30 EST 2012. Contains 206009 sequences.