build open-axiom
)cl all g:=operator 'g f==n+->sum(g(j),j=1..n) f(1) f==n+->product(sum(1/i,i=1..j),j=1..n) f(1) f==n+->product(product(1/i,i=1..j),j=1..n) f(1) f==n+->sum(sum(1/i,i=1..j),j=1..n) f(1)