id:A124989 - OEIS Search Results

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Primes of the form 10k+9 generated recursively. Initial prime is 19. General term is a(n)=Min {p is prime; p divides 100Q^2-5; Mod[p,10]=9}, where Q is the product of previous terms in the sequence.

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19, 7219, 462739, 509, 129229, 295380580489, 9653956849, 149, 110212292237172705230749846071050188009093377022084806290042881946231583507557298889, 157881589, 60397967745386189, 1429, 79 (list; graph; listen)

	OFFSET	`1,1`
	COMMENT	`100Q^2-5 always has a prime divisor congruent to 9 modulo 10.`
	LINKS	`N. Hobson, Home page (listed in lieu of email address)`
	EXAMPLE	`a(3) = 462739 is the smallest prime divisor congruent to 9 mod` `10 of 100Q^2-5 = 1881313992095 = 5 * 462739 * 813121, where Q = 19 * 7219.`
	CROSSREFS	`Cf. A000945, A030433, A057204-A057208, A051308-A051335, A124984-A124993, A125037-A125045.` `Sequence in context: A099809 A013724 A067267 this_sequence A093400 A110392 A107100` `Adjacent sequences: A124986 A124987 A124988 this_sequence A124990 A124991 A124992`
	KEYWORD	`more,nonn`
	AUTHOR	`Nick Hobson Nov 18 2006`

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Last modified July 23 17:35 EDT 2008. Contains 142285 sequences.

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