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Search: id:A160758
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| A160758 |
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Integer averages of n nonprimes for some n. |
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+0
1
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| 1, 8, 25, 33, 359, 2948, 3291, 4959, 22350, 33357, 60907, 80962, 8276347, 11856980, 15254419, 176009996
(list; graph; listen)
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OFFSET
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1,2
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FORMULA
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1/n*Sum {j=1..n} NonPrime_j is an integer. [From Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 05 2009]
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MATHEMATICA
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lst = {}; s = 0; c = 0; k = 1; While[k < 2700000000, If[ !PrimeQ@k, c++; s = s + k; If[Mod[s, c] == 0, AppendTo[lst, s/c]]]; k++ ]; lst [From Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 05 2009]
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CROSSREFS
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Cf. A050248, integer averages of n primes for some n
This occurs for the first k non-primes: A129749. [From Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 05 2009]
Sequence in context: A030796 A116086 A042611 this_sequence A163862 A015804 A161448
Adjacent sequences: A160755 A160756 A160757 this_sequence A160759 A160760 A160761
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KEYWORD
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easy,nonn,more
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AUTHOR
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Daniel Tisdale (daniel6874(AT)gmail.com), May 25 2009
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EXTENSIONS
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a(6) - a(16) from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 05 2009
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