Definition mbed_tls_fround (cols : four_ints) (rks : list Z) (i : Z) : four_ints :=
match cols with (col0, (col1, (col2, col3))) =>
  ((mbed_tls_fround_col col0 col1 col2 col3 (Znth  i    rks 0)),
  ((mbed_tls_fround_col col1 col2 col3 col0 (Znth (i+1) rks 0)),
  ((mbed_tls_fround_col col2 col3 col0 col1 (Znth (i+2) rks 0)),
   (mbed_tls_fround_col col3 col0 col1 col2 (Znth (i+3) rks 0)))))
end.

Lemma mbed_tls_fround_def: mbed_tls_fround = fun (cols : four_ints) (rks : list Z) (i : Z) => match cols with (col0, (col1, (col2, col3))) => ((mbed_tls_fround_col col0 col1 col2 col3 (Znth i rks 0)), ((mbed_tls_fround_col col1 col2 col3 col0 (Znth (i+1) rks 0)), ((mbed_tls_fround_col col2 col3 col0 col1 (Znth (i+2) rks 0)), (mbed_tls_fround_col col3 col0 col1 col2 (Znth (i+3) rks 0))))) end.