Sometimes when I come across a new number I factorise it, just for kicks. So when the year ticked over that’s what I tried doing.
It is intuitive that 2015 is divisible by 5, so I quickly decomposed it into 5 times 403. And then my intuitive reaction was “403 looks prime. So 2015 is such an uninteresting number”.
But then doing the rigorous analysis (dividing 403 by all primes <= 20 (= sqrt (403)), I figured that it goes by 13, and can be decomposed into 13 and 31, which makes it quite interesting!
So 2015 is a product of 5, 13 and 31, which makes it interesting, in that it is a product of relatively small primes!
The year began well here in Bangalore. It started drizzling soon after the clocks ticked over 12, and this morning has also been what people might describe as “gloomy” but what I find to be absolutely romantic weather!
Wish you all a happy and prosperous 2015!