[factorial2.b -- compute factorials
(c) 2019 Daniel B. Cristofani
http://brainfuck.org/]

>>>>++>+[
    [
        >[>>]<[>+>]<<[>->>+<<<-]>+[
            [+>>[<<+>>-]>]+[-<<+<]>-[
                -[<+>>+<-]++++++[>++++++++<-]+>.[-]<<[
                    >>>[[<<+>+>-]>>>]<<<<[[>+<-]<-<<]>-
                ]>>>[
                    <<-[<<+>>-]<+++++++++<[
                        >[->+>]>>>[<<[<+>-]>>>+>>[-<]<[>]>+<]<<<<<<-
                    ]>[-]>+>>[<<<+>>>-]>>>
                ]<<<+[-[+>>]<<<]>[<<<]>
            ]>>>[<[>>>]<<<[[>>>+<<<-]<<<]>>>>>>>-[<]>>>[<<]<<[>+>]<]<<
        ]++>>
    ]<<++++++++.+
]

This program computes the factorials (https://oeis.org/A000142). Because this
sequence is infinitely long, this program doesn't terminate on its own; you will
have to kill it. This program is much faster than my earlier factorial program.