100 cls
110 bs = 10 : c1 = 0 : c2 = 0
120 for k = 1 to (bs^2)-1
130   c1 = c1+1
140   if k mod (bs-1) = (k*k) mod (bs-1) then c2 = c2+1 : print k;
150 next k
160 print
170 print "Trying ";c2;"numbers instead of ";c1;"numbers saves ";100-(100*c2/c1);"%"
180 end