2021

7 posts

Dec 30, 2021
Welcome 2022 – #7daysto2022
Last year we did #7daysto2021 to welcome 2021 by solving one puzzle a day. Let us do the same this year to welcome 2022!
Dec 11, 2021Math
Happy Numbers Visualization
In this article, we discuss happy numbers and a nice way to visualize them!
Sep 10, 2021Programming
Game of Life on an ANSI Terminal!
Code: https://github.com/rmadhuram/ascii-art/blob/main/src/anim/life.c
Jul 16, 2021Math
Dates in Arithmetic Progression
Can you find all dates that are in arithmetic progression?
Feb 24, 2021
Adios & Thanks for the memories, Fry’s!
Today I was saddened to hear that Fry’s Electronics is closing all their stores all across the US! In this post, Fry’s was not just an electronics store! Each outlet was a destination by itself with a unique theme. I am capturing some fond memories of all the Fry’s outlets I have visited. Fry’s was…
Feb 6, 2021
Bernify your pictures!
My Sunday afternoon hack – “Bernify your pictures!” http://geekraj.com/bernify I made this web-based tool to add Bernie to your pictures. I forked and tinkered with a photo editor based on Cropper.js/Vue, developed by Fengyuan Chen. Your images are not sent to any server. 100% privacy ensured. Once you add Bernie, you can take a screenshot…
Jan 27, 2021Math
Squares ending in xyxyxyxyxy
If a square number ( $a^2$ ) ends with xyxyxyxyxy, then xy should be one of 21, 29, 61, 69, 84, [Inspired by this Fermat’s Library LinkedIn post] To prove this, we first write $a = 5*10^9n+k$ Now, $a^2 = 25*10^{18}n^2 + 10^{10}nk + k^2$ Hence, the last 10 digits are determined by the last 10 digits of $k^2$ , $0 \leq k < 5*10^9$ . Although it is…

Today I was saddened to hear that Fry’s Electronics is closing all their stores all across the US! In this post, Fry’s was not just an electronics store! Each outlet was a destination by itself with a unique theme. I am capturing some fond memories of all the Fry’s outlets I have visited. Fry’s was…

Bernify your pictures!

My Sunday afternoon hack – “Bernify your pictures!” http://geekraj.com/bernify I made this web-based tool to add Bernie to your pictures. I forked and tinkered with a photo editor based on Cropper.js/Vue, developed by Fengyuan Chen. Your images are not sent to any server. 100% privacy ensured. Once you add Bernie, you can take a screenshot…

Squares ending in xyxyxyxyxy

If a square number (

a^2

) ends with xyxyxyxyxy, then xy should be one of 21, 29, 61, 69, 84, [Inspired by this Fermat’s Library LinkedIn post] To prove this, we first write

a = 5*10^9n+k

Now,

a^2 = 25*10^{18}n^2 + 10^{10}nk + k^2

Hence, the last 10 digits are determined by the last 10 digits of

k^2

0 \leq k < 5*10^9

. Although it is…