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A157848
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Corresponding values of arithmetic means of divisors of numbers from A007340.
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1
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1, 3, 28, 45, 84, 182, 270, 620, 546, 1240, 1330, 1638, 1260, 1365, 2660, 8128, 6200, 6200, 6944, 8190, 9310, 7560, 8190, 18600, 15120, 18620, 16380, 25935, 30240, 32760, 63700, 55860, 40950, 55800, 117800, 98208, 105664, 117800, 121030, 173600, 167400, 155610
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OFFSET
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1,2
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COMMENTS
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A007340 = numbers k such that the arithmetic mean of divisors of k is integer and equal to one of the divisors of this numbers.
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LINKS
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FORMULA
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EXAMPLE
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a(3) = 28, because 28 is arithmetic mean of divisors of A007340(3)=140 and also is divisor of 140.
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PROG
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[SumOfDivisors(n) / NumberOfDivisors(n): n in[A007340(n)] ]
(PARI) lista(kmax) = {my(f, s, d); for(k = 1, kmax, f = factor(k); s = sigma(f); d = numdiv(f); if(!(s % d) && denominator(d / sigma(f, -1)) == 1, print1(s/d, ", "))); } \\ Amiram Eldar, Apr 15 2024
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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