Some pianists have an innate sense of poetic grace; others spend a lifetime trying to develop one. Portuguese pianist Sequeira Costa, on the strength of his concert last night at the Kennedy Center Terrace Theater, obviously belongs in the former category.

Almost from start to finish, Sequeira's eloquence was in keeping with the music at hand. In addition, he sacrificed no power in achieving this end. The one exception occurred during the first movement of Beethoven's Sonata No. 4 in E-flat Major, Op. 7, when his unwarranted percussive attack occasionally hammered instead of blended the lines. By the time he arrived at the Schubertian trio and the Rondo, however, his execution was nearly flawless.

Sequeira's finest moments came in Schumann's "Forest Scenes," Op. 82, and, especially, in Ravel's "Miroirs." He carefully weighed each of the nine hunt scenes, conveying Schumann's evanescent imagery with an assured touch. His "Bird as Prophet" sang with delicacy, while his "Hunting Song" contained the energy of a steed in hot pursuit of the game.

In "Miroirs," Sequeira performed with bold, masterly strokes. He pumped lifeblood into Ravel's five descriptive pieces, so that the "Nocturnal Moths" section flitted about with impressionistic fancy; the "Boat on the Ocean" segment glowed thanks to liquid phrasing and fully resonant overtones.

Portuguese composer Vianna da Motta's Lisztian showpiece, Ballada, Op. 6, and Albe'niz's fiery "Triana" from "Iberia" tested Sequeira's bravura technique, of which he had more than an ample store. He carried off his two encores by Chopin and Moszkowski with panache and finesse.