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 A181121 As n increases, the reciprocal of a(n) = asymptotic fraction of positive integers whose longest string of consecutive divisors is A181062(n). 1
 2, 3, 12, 15, 70, 840, 1260, 2772, 30030, 720720, 765765, 12932920, 243374040, 6692786100, 40156716600, 83181770100, 2406725881560, 144403552893600, 148414762696200, 5476504743489780, 224275908542914800 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The asymptotic average, as n increases, of n's longest string of consecutive divisors is the constant 1.787780456..., given in A064859. LINKS FORMULA a(n) = A051451(n) * A025473(n+1)/(A025473(n+1)-1). If A181062(n) = 2^(e-1), then a(n) = A003418(2^e) = A051451(n+1). EXAMPLE A number's longest string of consecutive divisors is a(5)=6 iff the integer is a multiple of 60 but not of 7. As n increases, the asymptotic fraction of positive integers satisfying those conditions equals 1/60 * 6/7 = 1/70. Therefore a(5) = 70. CROSSREFS Sequence in context: A124486 A260908 A123761 * A333319 A047163 A046486 Adjacent sequences:  A181118 A181119 A181120 * A181122 A181123 A181124 KEYWORD easy,nonn AUTHOR Matthew Vandermast, Oct 07 2010 STATUS approved

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Last modified December 2 10:39 EST 2020. Contains 338876 sequences. (Running on oeis4.)