Talk:Klarner-Rado sequence: Difference between revisions
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(Value of the 1 millionth item) |
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Is there an authoritative source for the value of the 1 millionth item in the sequence. My computer is telling me it is 52,102,239. It is not often wrong.--[[User:Nigel Galloway|Nigel Galloway]] ([[User talk:Nigel Galloway|talk]]) 10:53, 19 August 2022 (UTC)
:I can't find any independent confirmation of the value of the 1 millionth term but, FWIW, I'm as sure as I can be that it's 54,381,285. I just tried running the Wren example to a limit of 1.2 million to make sure there was nothing unexpected going on here but still got the same answer for the millionth.
:Your figure of 52,102,239 is the 963,815th element. --[[User:PureFox|PureFox]] ([[User talk:PureFox|talk]]) 12:45, 19 August 2022 (UTC)
:The other samples that go to the millionth element also show it as 54,381,285. --[[User:Tigerofdarkness|Tigerofdarkness]] ([[User talk:Tigerofdarkness|talk]]) 13:24, 19 August 2022 (UTC)
:My suspicion (though I haven't confirmed it) is that you are accumulating the x2 and x3 terms off of the same indexer so, when you reach 1e6th, you have excess x3 elements and a shortage of x2. The reason the earlier figures match is you have accumulated enough terms past it to have filled in any "gaps". I have also failed to find a 3rd party trusted source, but we now have at least 6 different implementations by at least 4 different authors that all agree on 54,381,285. Still not authoritative but circumstantial evidence is getting pretty convincing. --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 15:02, 19 August 2022 (UTC)
::Nothing so exciting, it just need 64bit integers.--[[User:Nigel Galloway|Nigel Galloway]] ([[User talk:Nigel Galloway|talk]]) 11:48, 22 August 2022 (UTC)
BTW, I just used a "bit-vector" as suggested by the Julia sample and it would seem that you need around 1.1 billion bits (137 500 000 bytes) to find the 10 millionth element, which I think is 1,031,926,801.
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The final element below 1.1 billion is element 10,543,878 which appears to be 1,099,640,002. --[[User:Tigerofdarkness|Tigerofdarkness]] ([[User talk:Tigerofdarkness|talk]]) 13:24, 19 August 2022 (UTC)
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