https://asciinema.org/a/3EjbNuCJ3D4ok81RWD1lyezwC - brain-even
https://asciinema.org/a/dKLxXEJP0VSdOsY9QRXgIrqZU - brain-calc
https://asciinema.org/a/ZeG33eSJGvOdRYEKnPKYZH1yP - brain-gcd
https://asciinema.org/a/TmEn1c5CnOcd0dD4UHStuUyR5 - brain-progression
https://asciinema.org/a/RCQjJALA3vqwPDmYlRf4ywovd - brain-prime