{def cache
 {def cache.F {#.new}}
 {def cache.M {#.new}}
 {lambda {:f :n}
   {let { {:f :f} {:n :n}
          {:cx {if {equal? :f MF}
                then {cache.F}
                else {cache.M}}}
        } {if {equal? {#.get :cx :n} undefined}
           then {#.get {#.set! :cx :n {:f :n}} :n}
           else {#.get :cx :n}}}}}
-> cache

{def MF
 {lambda {:n}
  {if {= :n 0}
   then 1
   else {- :n {MM {cache MF {- :n 1}}}}}}}
-> MF

{def MM
 {lambda {:n}
  {if {= :n 0}
   then 0
   else {- :n {MF {cache MM {- :n 1}}}}}}}
-> MM

{MF 80}
-> 50  (requires 55 ms)

{map MF {serie 0 100}}  (requires75ms)
-> 1 1 2 2 3 3 4 5 5 6 6 7 8 8 9 9 10 11 11 12 13 13 14 14 15 16 16 17 17
18 19 19 20 21 21 22 22 23 24 24 25 25 26 27 27 28 29 29 30 30 31 32 32
33 34 34 35 35 36 37 37 38 38 39 40 40 41 42 42 43 43 44 45 45 46 46 47
48 48 49 50 50 51 51 52 53 53 54 55 55 56 56 57 58 58 59 59 60 61 61 62