| 2 |
1. t' :
2. 0<t'
3. m: , T:Type, f:(  T), P:(T  ).
3. m+1 ||filter(P;map(f;upto(t'-1)))||
3. 
3. ( t: . P(f(t)) & ||filter(P;map(f;upto(t)))|| = m )
m: , T:Type, f:(  T), P:(T  ).
m+1 ||filter(P;map(f;upto(t')))||

( t: . P(f(t)) & ||filter(P;map(f;upto(t)))|| = m )
 | 7 steps |