A119730 - OEIS

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A119730

Primes p such that p+1, p+2, p+3, p+4 and p+5 have equal number of divisors.

13781, 19141, 21493, 50581, 142453, 152629, 253013, 298693, 307253, 346501, 507781, 543061, 845381, 1079093, 1273781, 1354501, 1386901, 1492069, 1546261, 1661333, 1665061, 1841141, 2192933, 2208517, 2436341, 2453141, 2545013 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	EXAMPLE	`13781 is OK since 13782, 13783, 13784, 13785 and 13786 all have 8 divisors:` `{1,2,3,6,2297,4594,6891,13782}, {1,7,11,77,179,1253,1969,13783},` `{1,2,4,8,1723,3446,6892,13784}, {1,3,5,15,919,2757,4595,13785} and` `{1,2,61,113,122,226,6893,13786}.`
	MATHEMATICA	`Select[Prime@Range[1000000], DivisorSigma[0, #+1]==DivisorSigma[0, #+2]==DivisorSigma[0, #+3]==DivisorSigma[0, #+4]==DivisorSigma[0, #+5]&]`
	CROSSREFS	`Cf. A008329, A049234.` `Sequence in context: A178486 A205259 A031807 * A204839 A188102 A109102` `Adjacent sequences: A119727 A119728 A119729 * A119731 A119732 A119733`
	KEYWORD	`nonn`
	AUTHOR	`Zak Seidov (zakseidov(AT)yahoo.com), Jul 29 2006`

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Last modified February 14 23:44 EST 2012. Contains 205689 sequences.