A100923 - OEIS

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A100923

a(n) = 1 iff 6*n+1 and 6*n-1 are both prime numbers (0 otherwise).

1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..105.`
	EXAMPLE	`a(3) = 1 because 63-1=17 and 63+1=19 are both prime.` `a(4) = 0 because 64-1=23 is prime and 64+1=25 is not prime.` `a(20) = 0 because 620-1=119 and 620+1=121 are both not prime.`
	MATHEMATICA	`Table[If[And[PrimeQ[6k - 1], PrimeQ[6k + 1]], 1, 0], {k, 1, 110}]`
	CROSSREFS	`Cf. A000040, A100924, A100925.` `Sequence in context: A083187 A080339 A167752 * A050073 A120474 A098370` `Adjacent sequences: A100920 A100921 A100922 * A100924 A100925 A100926`
	KEYWORD	`nonn`
	AUTHOR	`Joseph Biberstine (jrbibers(AT)indiana.edu), Nov 22 2004`
	STATUS	`approved`

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Last modified May 24 07:09 EDT 2013. Contains 225617 sequences.