CREATE TABLE table_52015 ("D 40 \\u221a" TEXT, "D 41 \\u221a" TEXT, "D 42 \\u221a" TEXT, "D 43 \\u221a" TEXT, "D 44 \\u221a" TEXT, "D 45 O" TEXT, "D 46 O" TEXT, "R 53 +" TEXT, "R 52 +" TEXT, "R 51 +" TEXT)

Name the D 45 O which has R 51 + of d 30
SELECT "D 45 O" FROM table_52015 WHERE "R 51 +" = 'd 30'
SELECT "D 45 O" FROM "table_52015" WHERE "R 51 +" = 'd 30'