Current State ID: 17
Current State Description: The hand is holding block 'a'. Block 'b' is clear and on the table. Block 'c' is clear and on the table. Block 'd' is clear and on the table. Block 'a' is no longer on the table; it is in the hand.

Child State ID: 19
Action Taken: stack(a, c)
State Description: The hand is empty. Block 'a' is on top of block 'c'. Block 'a' is clear. Block 'b' is clear and on the table. Block 'c' is not clear and on the table. Block 'd' is clear and on the table.

Child State ID: 20
Action Taken: put-down(a)
State Description: The hand is empty. Block 'a' is clear and on the table. Block 'b' is clear and on the table. Block 'c' is clear and on the table. Block 'd' is clear and on the table.

