* Example for n with the units identical 

bind
  lambda 10*(10^4)
  mu 1.25*10^6
end

block try(k,n) 
comp Unit ss_unavail(lambda, mu)
kofn sys k,n,Unit
end

func U(k,n) sysprob(try;k,n)
func A(k,n) 1-U(k,n)
func bin(k,n) sysprob(try;k+1,n)-sysprob(try;k,n)
func E(k,n) A(k,n)
func F(k,n) bin(k,n)*lambda*k

* Mean Time To System Failure
func MTTSF(k,n) E(k,n)/F(k,n)
* Mean Time To System Restoration
func MTTSR(k,n)  U(k,n) * MTTSF(k,n) / A(k,n)
func MTTSR1(k,n)  (1-E(k,n))/F(k,n)


* vary the value k
bind valN 4
loop k,1,3  
  expr  A(k,valN),U(k,valN), MTTSF(k,valN), MTTSR(k,valN), MTTSR1(k,valN)
end 

end
