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 A091440 Smallest number m such that m#/phi(m#) >= n, where m# indicates the primorial (A034386) of m and phi is Euler's totient function. 2
 1, 2, 3, 7, 13, 23, 43, 79, 149, 257, 461, 821, 1451, 2549, 4483, 7879, 13859, 24247, 42683, 75037, 131707, 230773, 405401, 710569, 1246379, 2185021, 3831913, 6720059, 11781551, 20657677, 36221753, 63503639, 111333529, 195199289 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Does the ratio of adjacent terms converge? For n > 1, a(n) is smallest prime p = prime(k) such that not less than (n-1)/n of any p# consecutive integers are divisible by a prime not greater than p. Cf. A053144(k)/A002110(k). - Peter Munn, Apr 29 2017 LINKS Eric Weisstein's World of Mathematics, Totient Function Eric Weisstein's World of Mathematics, Primorial EXAMPLE 7#/phi(7#) = (2*3*5*7)/(1*2*4*6) = 4.375 >= 4, 5#/phi(5#) = 3.75. Hence a(4) = 7. MATHEMATICA prod=1; i=0; Table[While[prod= mm, print1(x", "); mm++)); /* This will generate all terms of this sequence from the 3rd onward, up to lim. The computation slows down for large values because of the size of the internal values. */ - Fred Schneider, Aug 13 2009, modified by Franklin T. Adams-Watters, Aug 29 2009 CROSSREFS Cf. A091439, A000010, A002110, A034386, A053144, A038110, A060753, A164347. Sequence in context: A144104 A088175 A271827 * A175211 A075058 A213968 Adjacent sequences:  A091437 A091438 A091439 * A091441 A091442 A091443 KEYWORD nonn AUTHOR T. D. Noe, Jan 09 2004 EXTENSIONS More terms from David W. Wilson, Sep 28 2005 Sequence reference in name corrected by Peter Munn, Apr 29 2017 STATUS approved

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Last modified November 19 11:04 EST 2017. Contains 294936 sequences.