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A217867 Extremely abundant numbers: a(1)=10080; thereafter a(n) is a term if for n > m >= 1, sigma(a(n))/(a(n) log log a(n)) > sigma(a(m))/(a(m)log log a(m)). 2
10080, 8201519488959040182625924708238885435575055666675808000, 1041592975097798103193492437946338450318032069667827616000, 136448679737811551518347509370970336991662201126485417696000, 18693469124080182558013608783822936167857721554328502224352000, 2598392208247145375563891620951388127332223296051661809184928000, 5196784416494290751127783241902776254664446592103323618369856000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
If a(n) is an extremely abundant number, then it is superabundant.
LINKS
Sadegh Nazardonyavi, Extremely abundant number
S. Nazardonyavi, S. Yakubovich, Extremely Abundant Numbers and the Riemann Hypothesis, Journal of Integer Sequences, 17 (2014), Article 14.2.8.
CROSSREFS
A subset of A004394, A004490.
Sequence in context: A145836 A190293 A179729 * A157288 A230033 A252052
KEYWORD
nonn,changed
AUTHOR
Sadegh Nazardonyavi, Oct 27 2012
STATUS
approved

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Last modified May 27 07:52 EDT 2024. Contains 372850 sequences. (Running on oeis4.)