Talk:Untouchable numbers: Difference between revisions
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By running the Go program with a limit of 1e6 and a sieve factor of 20 (up from 14 for 1e5), I was in fact able to verify the figure of 150,232. Factors of 18 and 19 both gave 150,233 so there must be an 'awkward' number within this range which takes some eliminating. --[[User:PureFox|PureFox]] ([[User talk:PureFox|talk]]) 09:36, 11 February 2021 (UTC) |
By running the Go program with a limit of 1e6 and a sieve factor of 20 (up from 14 for 1e5), I was in fact able to verify the figure of 150,232. Factors of 18 and 19 both gave 150,233 so there must be an 'awkward' number within this range which takes some eliminating. --[[User:PureFox|PureFox]] ([[User talk:PureFox|talk]]) 09:36, 11 February 2021 (UTC) |
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I've managed to isolate the 'awkward' number which is 816,422. The (first) number whose proper divisors sum to this is 19,175,641 its divisors being [1, 29, 151, 841, 4379, 22801, 126991, 661229]. This explains why we need a sieve factor between 19 and 20 to catch it since neither 816,421 or 816,419 is prime. --[[User:PureFox|PureFox]] ([[User talk:PureFox|talk]]) 11:33, 11 February 2021 (UTC) |
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