id:A087685 - OEIS Search Results

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Primes n such that 5^n-4^n is composite.

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2, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 47, 53, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 193, 197, 199, 211, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307 (list; graph; listen)

	OFFSET	`1,1`
	PROGRAM	`(PARI) apmb(a, b, n) = { forprime(x=2, n, y=a^x-b^x; if(!ispseudoprime(y), print1(x", "); ) ) }`
	CROSSREFS	`Sequence in context: A118751 A137519 A045344 this_sequence A020619 A165439 A020591` `Adjacent sequences: A087682 A087683 A087684 this_sequence A087686 A087687 A087688`
	KEYWORD	`nonn`
	AUTHOR	`Cino Hilliard (hillcino368(AT)gmail.com), Oct 26 2003`
	EXTENSIONS	`Checked by Ray Chandler, Apr 24 2007`

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Last modified December 7 08:40 EST 2009. Contains 170430 sequences.

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