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May 23

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Sequence

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147-2, 137-1, 340-7 what's the next two numbers in this sequence and what formula is being used? Thanks. — Preceding unsigned comment added by 41.212.16.230 (talk) 07:05, 23 May 2020 (UTC)[reply]

There exist an infinite amount of sequences, an infinite amount of sequences that contain your subsequence, and an infinite amount of possible continuations. The great Tibees recently joked about these kind of questions by fitting an excessively complex polynomial to the ordinary sequence 1,4,7,10 leading to the ridiculous but correct answer of 314 instead of the expected 13. https://www.youtube.com/watch?v=IXojoV9fngY&t=226s--TZubiri (talk) 08:00, 23 May 2020 (UTC)[reply]
It is meaningful to seek a formula with minimum description length.  --Lambiam 14:39, 23 May 2020 (UTC)[reply]
While Lambiam is of course right, there is always Carl Linderholm's Mathematics Made Difficult to give a laugh too, discussing the sequence 1, 2, 4, 8, 16, ___:
XD Double sharp (talk) 07:11, 25 May 2020 (UTC)[reply]
Is anything known about the context? Is this from an intelligence test of some kind? Numbers are usually not written with hyphens, so why are these three items called numbers? Or is it subtraction – but if so, then why not ask simply about 145, 136, 333? The only simple regularity I see is that (1+4+7) mod 10 = 2, (1+3+7) mod 10 = 1 and (3+4+0) mod 10 = 7. But this may well be a coincidence and, moreover, is not helpful for finding a next item.  --Lambiam 14:39, 23 May 2020 (UTC)[reply]
I guess it's viewed as pairs of two numbers where "-" may or may not represent subtraction, and the goal is one more pair a-b (or a+b?). I haven't found a plausible answer. PrimeHunter (talk) 13:18, 24 May 2020 (UTC)[reply]

Relationship between manifolds and arrays.

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A sequence is 1 dimensional, a matrix is 2 dimensional, what do we call 3 dimensional and n-dimensional objects? My best guess here is arrays, but these are terms from computer science, what were these called before computers? Also, aren't sequences better described as 2dimensional and matrices as 3 dimensional? A scalar would be 1d and a boolean would be 0d. A sequence would be roughly analogous to a line on a plane in this case. And by roughly analogous I mean that they contain a similar amount of information, and they can be accurately mapped in both directions (by mapping each element in a sequence to a point in a whose coordinates are determined by the ordinal and value of the element). And which of these should be considered a more accurate representation of a real world phenomenon? On one hand, a manifold contains more information, an infinite amount, on the other hand (if Democritus atomism hypothesis is to be believed), there is no infinite complexity in the real world and an array would be the most faithful representation of physical matter. --TZubiri (talk) 07:45, 23 May 2020 (UTC)[reply]

See Holor. (The holor! The holor!)  --Lambiam 13:58, 23 May 2020 (UTC)[reply]
You are probably thinking of tensors. 2601:648:8202:96B0:3567:50D5:8BFF:4588 (talk) 04:16, 25 May 2020 (UTC)[reply]