atiyah.jl

# Compute the nth elementary symmetric function (elementary symmetric polynomial) of a a 1D iterable x
# This is the THIRD esf
function esf(n, x)
  summand = zero(eltype(x))
  for j1 = 1:n, j2 = 1:j1-1, j3 = 1:j2-1
    summand += x[j1]*x[j2]*x[j3]
  end
  return summand
end

function bernoulli(k, γ)
   n = length(γ)
   c = zeros(k)
   for i=1:k
     c[i] = esf(i, x)
   end
   return factorial(k)*(-1)^k*todd(k, c)
end