I gotta be that guy: Why is this the first post on the front page of Hacker News? Is basic arithmetic really so fascinating to the computer people?
1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
71–80 of 109 posts
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#72Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#73http://blog.zyrthofar.com/2012/07/multiplying-recurring-deci...
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#74The pattern will break down once you get past 8192, which is 2^13. That means that the pattern continues for an impressive 52 significant figures (well, it actually breaks down on the 52nd digit, which will be a 3 instead of a 2). The reason it works is that 9998 = 10^4 - 2. You can expand as 1 / (10^n - 2) = 1/10^n * 1/(1 - 2/10^n) = 1/10^n * (1 + 2/10^n + 2^2 /10^2n + 2^3 /10^3n + ...) which gives the observed patt…
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#75In high school, I was pretty fond of plugging 11^n to get rows of Pascal's triangle. It breaks down at row 5, but inserting 0's in the middle extends it (e.g. 101^n, 1001^n, 10001^n). 11^0 1 11^1 1 1 11^2 1 2 1 11^3 1 3 3 1 11^4 1 4 6 4 1
Needless to say, I didn't get it, but one guy in our class, like an 8th grader, did. He was pretty smart.
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#76Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#77echo "scale=10000;1/999999999999999999999999998" | bc
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#78Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#79Wolfram Alpha interprets 1/0x9999998 or 1/0xffffffe correctly as hex input, but still shows the output as decimal approximation, while a hexadecimal approximation would be more useful here. I would be really curious what this thing looks like in other numeric bases.
Unfortunately, the "Other base conversions" section only shows up to 7 or so digits after the point and doesn't allow expanding.
EDIT: found it! I didn't know bc in linux was this awesome! echo "obase=16;ibase=16;scale=1000;1/FFFE" | bc .0001000200040008001000200040008001000200040008001000200040008001000 (....)
Re: 1/9998 = 0.0001 0002 0004 0008 0016 0032 0064 0128 0256..
#80I gotta be that guy: Why is this the first post on the front page of Hacker News? Is basic arithmetic really so fascinating to the computer people?