prog.sf

#!/usr/bin/ruby

# a(n) is the maximum prime factor of the concatenation of all the previous terms, with a(1)=1, a(2)=2.
# https://oeis.org/A280893

include('../../../factordb/auto.sf')

func a(n) is cached {
    return 1 if (n == 1)
    return 2 if (n == 2)
    gpf(Num(1..^n -> map(a).join))
}

var fh = File('bfile.txt').open_w

fh.autoflush(true)

for n in (1..10000) {
    var row = "#{n} #{a(n)}"
    say row
    fh.say(row)
}

__END__