What is the horizontal bar score with a pommel horse of n/a, and the position is less than 27, and the parallel bars score is 15.800?
CREATE TABLE "individuals" (
  "position" real,
  "gymnast" text,
  "floor" text,
  "pommel_horse" text,
  "rings" text,
  "vault" text,
  "parallel_bars" text,
  "horizontal_bar" text,
  "total" real
);
SELECT "horizontal_bar" FROM "individuals" WHERE "pommel_horse"='n/a' AND "position"<27 AND "parallel_bars"='15.800';