[julia-users] Error: expected Function, got Int64

[Daniel Høegh]

Have you tried to restart the REPL, because I see no problems in running:
function fib_sum_2(x,y,z)
    sum(x:x:z) + sum(y:y:z) - sum(lcm(x,y):lcm(x,y):z)
end
julia> fib_sum_2(3,5,999)
233168