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A215264
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Numbers k such that sigma(k) > 5*k.
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8
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122522400, 147026880, 183783600, 205405200, 220540320, 232792560, 245044800, 273873600, 294053760, 328648320, 367567200, 410810400, 428828400, 441080640, 465585120, 490089600, 492972480, 497296800, 514594080, 537213600, 547747200, 551350800, 563603040
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OFFSET
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1,1
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COMMENTS
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The asymptotic density of this sequence is > 1/a(1) ~ 8*10^(-9). Wall et al. (1972) proved that it is < 0.0122. - Amiram Eldar, Feb 13 2021
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LINKS
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Gordon L. Miller and Mary T. Whalen, Multiply Abundant Numbers, School Science and Mathematics, Volume 95, Issue 5 (May 1995), pp. 256-259.
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FORMULA
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EXAMPLE
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sigma(122522400) = 614210688 and 614210688 > 5 * 122522400.
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PROG
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(PARI) for(n=122522400, 563603040, if(sigma(n)>5*n, print1(n ", ")))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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