E(n;F) == if (n = 0) then F(null) else weighted-sum(p;x.E(n - 1;rv-shift(x;F))) fi 

---

clarification:

expectation(p;n;F)
== if (n = 0) then F(null) else weighted-sum(p;x.expectation(p;n - 1;rv-shift(x;F))) fi 
(recursive) 

latex

Definitions	Y, if b then t else f fi , (i = j), null, weighted-sum(p;F), x.A(x), f(a), n - m, #$n, rv-shift(x;X)
FDL editor aliases	expectation