Unlimited Voice + Data* + TXT 2-line family plans in the US
Simple table of current US pricing among wireless service providers.
steve's alternative recursion
stuff from my brainAnother Fun Puzzle
The prime number 4535653, when translated to base 16, gives the hexadecimal number 0×453565, which has the same digits as the original number, omitting the last digit.
Find another example of a prime number that, translated to hexadecimal, yields the same digits, omitting the last 21 digits
This was the Ponder This Challenge for April 2010.
It relies on positional base numeral systems which are widely used and rarely thought about in our culture.
Buying an LCD Display
I decided I wanted a 24” display, so i did a little searching.
I settled on the HP ZR24w, as it was an IPS panel with good colors and viewing angles (IPS panel), had very little input lag, could rotate for 16:10 or 10:16 use, and wasn’t ridiculously priced like most IPS panels.
on HP’s page they are boasting a lot of energy saving stuff like an 85% power supply. But forgive me for not really trusting their energy-efficient marketing, so I started comparing some LCD power consumption and found some striking differences. Take a look at the little table I constructed:
other sources:
What a wide range of power consumption, even at the same brightness. There are no sanely-priced efficient IPS-panel 24-inch displays. On this data it seems LEDs use less energy (no surprise), but maybe IPS panels need more power than tn? I say that because the apple display is LED and IPS and still guzzles watts (oddly even more than the dell IPS ccfl display).
Factoring Algorithm puzzle
What is the minimal number, X, of yes/no questions needed to find the smallest positive integer divisor (other than 1) of an integer between 2 and 166 (inclusive)?
We are asking for the exact answer in two cases:
- In the worst case, i.e., what is the smallest number X for which we can guarantee finding it in no more than X questions.
- On average, i.e., assuming that the number was chosen in uniform distribution from 2 to 166 and we want to minimize the expected number of questions.
This problem was IBM’s Ponder This puzzle of November 2009.
I’m going to write my solution in English, along with code (both python and java) so anyone knowing any one of the 3 languages should be able to follow along.
the Quantitative GRE has a Quantitative failure:
The quantitative exam lumps a large portion of test takers with a significant variation in ability into a single score.
The verbal does not have a similar flaw.
the results from everyone who is trying to get into a graduate program:
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clearly there is a problem here where the most common score of all test-takers is the maximum.
let’s take a closer look at how this makes the GRE Quantitative even less useful for specific graduate programs:
test
if x>y:
print("success")
if x<y:
print("failure")