id:A127957 - OEIS Search Results

Search: id:A127957

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Numbers n such that (2^prime(n)+1)/3 is composite.

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13

10, 12, 13, 15, 16, 17, 19, 20, 21, 23, 24, 25, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89 (list; graph; listen)

	OFFSET	`1,1`
	MATHEMATICA	`a = {}; Do[c = (2^Prime[x] + 1)/3; If[PrimeQ[c] == False, AppendTo[a, x]], {x, 2, 300}]; a`
	CROSSREFS	`Cf. A000979, A000978, A124400, A126614, A127955, A127956.` `Sequence in context: A083476 A124404 A031288 this_sequence A079026 A124867 A161598` `Adjacent sequences: A127954 A127955 A127956 this_sequence A127958 A127959 A127960`
	KEYWORD	`nonn`
	AUTHOR	`Artur Jasinski (grafix(AT)csl.pl), Feb 09 2007`

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Last modified December 15 00:47 EST 2009. Contains 170825 sequences.

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