CREATE TABLE table_39814 ("Year" FLOAT, "Mission type" TEXT, "Shogun" TEXT, "Ry\\u016bky\\u016ban King" TEXT, "Lead Envoy" TEXT, "Number in entourage" TEXT)

Who was the lead envoy of the congratulation mission in 1718 with the Ry ky an King sh kei?
SELECT "Lead Envoy" FROM table_39814 WHERE "Ry\u016bky\u016ban King" = 'shō kei' AND "Mission type" = 'congratulation' AND "Year" = '1718'
SELECT "Lead Envoy" FROM "table_39814" WHERE "Mission type" = 'congratulation' AND "Ry\u016bky\u016ban King" = 'shō kei' AND "Year" = '1718'