Category: mathematics

  • Doing some estimations

    This is again one of those topics which I like to rant about, so I give you the short version: when you see a number, question it! Most of the numbers thrown at us in different media can be disproven quite easily and it is our responsibility as people not to just repeat whatever we’ve…

  • Solving mathematical puzzles with brute-force and Perl

    After talking a lot about optimizations and selecting the right algorithm, here is a little brute-force code. This particular one gives the answer to the following puzzle from Richard Wiseman’s Blog (one well worth following BTW): Can you make the number 24 with the number 5, 5, 5, and 1 (again, you cannot join the…

  • Computing the last digit of b^e efficiently

    Geek PSA: Yesterday was PI day (3.14, get it?). Lets celebrate with this spiked math comic: Last week I saw the following problem which peaked my interest: Compute the last (decimal) digit of 2 raised to the power e where e might be very large. We assume that we are talking about positive, integer exponents…

  • Pi day and other ramblings

    The USA congress decided that March the 14th is national Pi day (from chuckchat.com). While I’m not a USA citizen and live nowhere near it, I still thought that the idea is cute. Math can be fun (even though the education systems gives the opposite impression frequently). A fun fact which I was amazed by…

  • All natural numbers are special

    From the department of too-geeky-joke-to-be-funny comes the following one: All natural numbers are special: 0 is special because it is the first natural number 1 is special because it is the neutral element for multiplication 2 is special because it is the first even number 3 is special because it is the first odd prime…