コンパイルエラー

./Main.cpp: In function 'constexpr std::array<std::array<atcoder::static_modint<998244353>, 2>, 4> e()':
./Main.cpp:7:43: error: invalid return type 'std::array<std::array<atcoder::static_modint<998244353>, 2>, 4>' of 'constexpr' function 'constexpr std::array<std::array<atcoder::static_modint<998244353>, 2>, 4> e()'
    7 | static constexpr array<array<mint, 2>, 4> e() {
      |                                           ^
In file included from /usr/include/c++/12/functional:63,
                 from /usr/include/x86_64-linux-gnu/c++/12/bits/stdc++.h:71,
                 from ./Main.cpp:1:
/usr/include/c++/12/array:99:12: note: 'std::array<std::array<atcoder::static_modint<998244353>, 2>, 4>' is not literal because:
   99 |     struct array
      |            ^~~~~
/usr/include/c++/12/array:115:56: note:   non-static data member 'std::array<std::array<atcoder::static_modint<998244353>, 2>, 4>::_M_elems' has non-literal type
  115 |       typename _AT_Type::_Type                         _M_elems;
      |                                                        ^~~~~~~~