brain-even https://asciinema.org/a/GncPGcqtqsOCTLO88mDzOCGjq
brain-calc https://asciinema.org/a/GncPGcqtqsOCTLO88mDzOCGjq
brain-gcd https://asciinema.org/a/GncPGcqtqsOCTLO88mDzOCGjq
brain-prime https://asciinema.org/a/GncPGcqtqsOCTLO88mDzOCGjq
brain-progression https://asciinema.org/a/GncPGcqtqsOCTLO88mDzOCGjq