The recently opened Sushi 7 (1026-A Coast Village Rd., 845-8923, sushi7sb.com) was named to take advantage of all the luck associated with the number seven. The number seven frequently appears in Japanese folklore: There are seven deities of good fortune, seven treasures, and seven reincarnations in Japanese Buddhism, to name a few. Each of Sushi 7’s signature rolls is a complex cornucopia, like the Montecito High Roller with soft-shelled crab, avocado, cream cheese, and cucumber topped with tuna, papaya, sun-dried tomato, red onion, mustard, and miso sauce. While the majority of the menu is devoted to ocean fare, from seaweed salad to seared tuna, there also are interesting alternatives like ahiru: a roasted duck crpe roll with pan-seared foie gras and lychee tarmarind drizzle. For simple palates, there are the usual offerings of nigiri sushi and sashimi. Check the specials for o-toro, uni, and live orange clams. Surprisingly, the don’t-miss entree is on the hot dish list: the black cod kasuzuke-sake-marinated roasted black cod with miso dressing-is so tender that it practically melts off your chopsticks.