#John Kim
#Use whatever you like

#read "C:/Users/John Y. Kim/Documents/Maple/hw18Special.txt":


Help:=proc():  print(`mex(S), a(n)`):
end:


#mex(S): inputs a set of non-negative integers and 
#outputs the smallest non-negative integer NOT in S.

mex:=proc(S) local m,i:

m:=max(S):

for i from 0 to m do
 if not i in S then
  RETURN(i):
 fi:
od:

RETURN(m+1): 

end:


a:=proc(n) local j,r:
option remember:

if n=1 then
 RETURN(2):
fi:

if n=2 then
 RETURN(3):
fi:

RETURN(mex({0,1} union {seq(seq(j*a(r),j=1..100), r=1..n-1)})):
end: