4 ms·
I was wondering if this had any implications for BB(6) but it seems that can't be written down exactly (not enough room in this universe) so BB(5) is the last o
by onraglanroad 1y ago
I was wondering if this had any implications for BB(6) but it seems that can't be written down exactly (not enough room in this universe) so BB(5) is the last one we'll see an exact value for.
- sapiogram 1y agoWikipedia give a lower bound for BB(6) of 2^2^2^2^2^2... repeated 33554432 times, that's definitely a fast-growing function!
- jojomodding 1y agoAnd it gets that figure from this paper and the authors of this paper continuing to work on BB(6).
- mostly_a_lurker 1y agoHmm, I think you might be a bit underestimating? My understanding of up-arrow notation is: 2 ^^^ 5 means 2 ^^ (2 ^^ (2 ^^ (2 ^^ 2))) (with five 2's) = 2 ^^ (2 ^^ (2 ^^ (2 ^ 2))) = 2 ^^ (2 ^^ (2 ^^ 4)) = 2 ^^ (2 ^^ 65536), since Wikipedia calculates 2 ^^ 4 = 65536. Now 2 ^^ 65536 means 2 ^ (2 ^ (2 ^ ...))) with 65536 two's. Call that number N (too large to really describe). Then 2 ^^ N is 2 ^ (2 ^ ( ...)) with N two's.