id:A074973 - OEIS Search Results

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Smallest index i such that NextPrime[p2 := 2*Prime[i]] - p2 = 2n - 1.

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1, 4, 11, 20, 17, 67, 104, 56, 125, 165, 182, 316, 236, 359, 407, 1254, 667, 836, 1521, 1210, 1966, 3197, 1520, 2294, 2279, 2046, 5410, 5472, 1965, 6702, 13947, 10138, 12122, 16760, 7659, 22325, 16784, 13072, 36169, 17852, 15414, 69872, 23814 (list; graph; listen)

	OFFSET	`1,2`
	COMMENT	`First index i such that NextPrime[p2=2Prime[i]]-p2 is 2n-1; case n=1 corresponds to Sophie Germain (SG) primes, others may be called SG n-primes. Distance between 2(n-th prime) and next prime in A059787.`
	EXAMPLE	`a(54) = 342337 because difference between 2p(342337) and next prime is 254 -1 = 107 and 342337 is the smallest such index.`
	CROSSREFS	`Cf. A059787.` `Sequence in context: A038431 A009908 A049935 this_sequence A025526 A047962 A047961` `Adjacent sequences: A074970 A074971 A074972 this_sequence A074974 A074975 A074976`
	KEYWORD	`nonn`
	AUTHOR	`Zak Seidov (zakseidov(AT)yahoo.com), Oct 06 2002`

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Last modified November 24 19:42 EST 2009. Contains 167435 sequences.

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