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Old 2011-01-26, 21:14   #23
axn
 
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Quote:
Originally Posted by davar55 View Post
Could someone solve for a,b,c,d,e,v,w,x,y,z ?
http://www.factordb.com/index.php?query=2^2011-1

Last fiddled with by axn on 2011-01-26 at 21:14
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Old 2011-01-27, 10:03   #24
Merfighters
 
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Quote:
Originally Posted by davar55 View Post
So the factors are p7 * p42 = 54491.....71953 * c558 = abcde.....vwxyz.

Could someone solve for a,b,c,d,e,v,w,x,y,z ?
This one?
(a,b,c,d,e,v,w,x,y,z)=(1,9,8,6,7,8,7,4,7,9)
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Old 2011-01-28, 16:52   #25
cmd
 
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p7 = 2171881
_42+
558=
____
6oo ckd
===

@ew .. we now return to good and stop ... he||o

.
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Old 2011-01-29, 10:56   #26
xilman
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Quote:
Originally Posted by davar55 View Post
Ah but my MPA calculator doesn't factor that high, so I'd have to let it
divide by the p7 and p42 first, which I'd have to key in.

And my electronic pocket calculators are FP-Scientific,
so I only get 1 bit of precision ( ).
Think about modular arithmetic.

In the late 70's, long before I had access to computers, I was doing these sorts of computations with a simple floating point calculator.

Paul
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Old 2011-01-31, 18:22   #27
ewmayer
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Quote:
Originally Posted by xilman View Post
Think about modular arithmetic.

In the late 70's, long before I had access to computers, I was doing these sorts of computations with a simple floating point calculator.
Yes, but were you using balanced-digit transform-based modmuls?
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Old 2011-01-31, 21:09   #28
xilman
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Quote:
Originally Posted by ewmayer View Post
Yes, but were you using balanced-digit transform-based modmuls?
No, but for evaluating the leading five and trailing five digits of a simple multiplication, division, remainder or exponentiation I didn't need to.

We had it tough. There was a time when I could do it on a slide rule though I then had to work in radix 1000 and take care to check the final digit with mental calculation.

Try telling the youth of today that, and they won't believe you.

Paul
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Old 2011-02-19, 22:44   #29
Flatlander
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Default Some soccer thingy by the local lads.

Crawley 0 - 1 Man Utd

Crawley did better than I thought they would, I guessed 1 - 5. Though Man Utd weren't on top form apparently.

An anagram:
Crawley rules ok.
=
Or we really suck.
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Old 2011-04-22, 19:11   #30
davar55
 
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Thanks for those factoring programs and dbs.

Collecting here a bit:

2^2011-1 =

2171881, 544919289684132720332849364364039531371953, *

If I counted digits on my fingers correctly, then:

2^2011-1 = p7 * p42 * c558

So it factors as: p7 * p42 = 54491.....71953 * c558 = 19867.....87479

I'll have to see how 2^2012-1 factors.

I doubt the world will end before I do.
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Old 2014-12-14, 04:07   #31
davar55
 
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With my multi-precision integer calculator:

2^2012-1 = C606 = 47027.....24095 = 3 * 5 * 6037 * 10061 * C597

C597 = 51617.....76289

From factordb, it is already completely factored.
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