SELECT 
  id_path 
FROM 
  cscart_categories 
WHERE 
  category_id IN (
    1585, 1600, 1620, 1641, 1804, 1857, 1861, 
    1926, 1935, 1939, 2001
  )

Query time 0.00062

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "p_category_id"],
      "key": "p_category_id",
      "key_length": "3",
      "used_key_parts": ["category_id"],
      "rows": 11,
      "filtered": 100,
      "index_condition": "cscart_categories.category_id in (1585,1600,1620,1641,1804,1857,1861,1926,1935,1939,2001)"
    }
  }
}

Result

id_path
1516/1517/1583/1585
1516/1517/1525/1600
1620
1641
1842/1843/1804
1842/1855/1857
1842/1860/1861
1920/1921/1926
1920/1933/1935
1920/1938/1939
2001