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 A080672 Numbers having divisors 2 or 3 or 5 or 7. 5
 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A020639(a(n)) <= 7; A210679(a(n)) > 0. - Reinhard Zumkeller, Apr 02 2012 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 FORMULA From Charles R Greathouse IV, Sep 14 2015: (Start) a(n) = 35n/27 + O(1). For n > 162, a(n) = a(n-162) + 210. [Corrected by Peter Munn, Apr 22 2021] (End) For n < 162, a(n) = 210 - a(162-n). - Peter Munn, Apr 22 2021 PROG (PARI) div2357(n)= for(x=1, n, if(gcd(x, 210)<>1, print1(x" ")) ) (PARI) is(n)=gcd(n, 210)>1 \\ Charles R Greathouse IV, Sep 14 2015 (Haskell) a080672 n = a080672_list !! (n-1) a080672_list = filter ((<= 7) . a020639) [2..] -- Reinhard Zumkeller, Apr 02 2012 CROSSREFS Cf. A020639, A008364 (complement). Subsequences: A002473, A343597. Sequence in context: A164713 A343185 A070331 * A056757 A225737 A079333 Adjacent sequences:  A080669 A080670 A080671 * A080673 A080674 A080675 KEYWORD easy,nonn AUTHOR Cino Hilliard, Mar 02 2003 EXTENSIONS Offset fixed by Reinhard Zumkeller, Apr 02 2012 STATUS approved

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Last modified September 16 18:26 EDT 2021. Contains 347473 sequences. (Running on oeis4.)