Question: What nationality was the composer who wrote 'The First Piano Sonata in 1946'?

Context paragraphs:
Piano sonata: A piano sonata is a sonata written for a solo piano.  Piano sonatas are usually written in three or four movements, although some piano sonatas have been written with a single movement (Scarlatti, Liszt, Scriabin, Medtner), two movements (Haydn), five (Brahms' Third Piano Sonata) or even more movements.  The first movement is generally composed in sonata form.

Pierre Boulez: Pierre Louis Joseph Boulez CBE (] ; 26 March 1925 – 5 January 2016) was a French composer, conductor, writer and organiser of institutions.  He was one of the dominant figures of the post-war classical music world.

Piano Sonata No. 3 (Beethoven): Ludwig van Beethoven's Piano Sonata No. 3 in C major, Op. 2, No. 3, is a sonata written for solo piano, composed in 1795.  It is dedicated to Joseph Haydn and is often referred to as Beethoven's first virtuosic piano sonata.  The three Opus 2 sonatas all contain four movements each, an unusual length which seems to show that Beethoven was aspiring towards composing a symphony.  It is both the weightiest and longest of the three Opus 2 sonatas, lasting over 25 minutes, presenting many difficulties, including difficult trills, awkward hand movements, and forearm rotation.  It is Beethoven's second longest piano sonata in his early period, only to Beethoven's Grand Sonata in E-flat Major, Op. 7, published a year later.

Piano Sonata No. 15 (Beethoven): Piano Sonata No. 15 in D major, Op. 28, is a piano sonata by Ludwig van Beethoven.  The name Pastoral or Pastorale became known through A. Cranz publishing of Beethoven's work, but was first coined by a London publisher, Broderip & Wilkinson.  While not as famous as its immediate predecessor, Piano Sonata No. 14, it is generally admired for its intricate technicality as well as for its beauty.  The sonata takes roughly twenty-five minutes to play with its intended repeats.

Piano Sonata No. 1 (Hindemith): Piano Sonata No. 1 in A major is the first piano sonata by German composer Paul Hindemith.  It was finished in 1936 and is subtitled Der Main (translated into English as The River Main) after a poem by Friedrich Hölderlin.

Piano Sonata No. 12 (Mozart): The Piano Sonata No. 12 in F major by Wolfgang Amadeus Mozart, K. 332/300k, was written at the same time as the Piano Sonata, K. 330, and Piano Sonata, K. 331 ("Alla turca"), Mozart numbering them as a set from one to three.  They were once believed to have been written in the late 1770s in Paris, but it is now thought more likely that they date from 1783, by which time Mozart had moved to Vienna.  Some believe that Mozart wrote this and the other sonatas during a summer 1783 visit to Salzburg made for the purpose of introducing his wife, Constanze to his father, Leopold.  All three sonatas were published in Vienna in 1784.

Piano Sonata No. 1 (Mozart): Wolfgang Amadeus Mozart's Piano Sonata No. 1 in C major, K.  279 / 189d (1774), is a piano sonata in three movements.  It was composed when Mozart was only 18 years old and is the first of a set of his 18 piano sonata.  All but 2 of the sonatas, No. 8 in A minor and No. 14 in C minor are in a major key.  Also, the first several sonatas seem to follow the cycle of fifths, to the flat side first (No. 1 in C major, No. 2 in F major, No. 3 in B-flat major, No. 4 in E-flat major) and then to the sharp side (No. 5 in G major, No. 6 in D major).

Piano sonatas (Boulez): Pierre Boulez composed three piano sonatas.  The First Piano Sonata in 1946, a Second Piano Sonata in 1948, and a Third Piano Sonata was composed in 1955–57 with further elaborations up to at least 1963, though only two of its movements (and a fragment of another) have been published.

Double-Function Form: Double-function form is a musical construction that allows for a collection of movements to be viewed as elements of a single larger musical form.  The most famous example of this is Franz Liszt’s Piano Sonata in B minor (1853).  The sonata is composed as a single movement with about a half an hour’s duration.  The piece introduces some themes at the very outset of the piece which are manipulated and recapitulated over twenty minutes later.  Charles Rosen believes that the work as whole fulfils his criterion for a sonata form.  Moreover, within the one long sonata form, there exists a short sonata form, followed by a slow ternary, followed by a scherzo and fugue, followed by a finale.  Thus, the single movement fulfills the standard of both a classical sonata form and a classical four movement piano sonata.

Piano Sonata No. 3 (Brahms): The Piano Sonata No. 3 in F minor, Op. 5 of Johannes Brahms was written in 1853 and published the following year.  The sonata is unusually large, consisting of five movements, as opposed to the traditional three or four.  When he wrote this piano sonata, the genre was seen by many to be past its heyday.  Brahms, enamored of Beethoven and the classical style, composed Piano Sonata No. 3 with a masterful combination of free Romantic spirit and strict classical architecture.  As a further testament to Brahms' affinity for Beethoven, the Piano Sonata is infused with the instantly recognizable motive from Beethoven's Symphony No. 5 during the first, third, and fourth movements.  Composed in Düsseldorf, it marks the end of his cycle of three sonatas, and was presented to Robert Schumann in November of that year; it was the last work that Brahms submitted to Schumann for commentary.  Brahms was barely 20 years old at its composition.  The piece is dedicated to Countess Ida von Hohenthal of Leipzig.

Supporting paragraphs: Piano sonatas (Boulez) Pierre Boulez
Answer: French