The last two examples need a more compact notation. The standard notation contains each of the different digits only one time, and its quantity in the exponent. So min(5,6)=(32*420) and min(5,5)=(412)
All numbers of the forms 3a*4b or 2*3a*4b must be checked. The only criteria is the 0er-criteria, because 5 is a prime. Maximal a+b, without holding the criteria was 47. All numbers with a+b<=20.000 were checked. Only the last 95 digits were needed.
