-- -*- M2-comint -*- {* hash: -611621507 *}

i1 : subsets 4

o1 = {{}, {0}, {1}, {0, 1}, {2}, {0, 2}, {1, 2}, {0, 1, 2}, {3}, {0, 3}, {1,
     ------------------------------------------------------------------------
     3}, {0, 1, 3}, {2, 3}, {0, 2, 3}, {1, 2, 3}, {0, 1, 2, 3}}

o1 : List

i2 :