Piano concertos by Wolfgang Amadeus Mozart it was probably J.C. Bach, whom Mozart admired, who introduced the structural innovation of allowing the keyboard to introduce new thematic material in its first entry. Concertos Nos 1–4 (K. 37, 39, 40 and 41) are orchestral and keyboard arrangements of sonata movements by other composers. The next three concertos (K. 107/1, 2 and 3), which are not numbered, are arrangements of piano sonatas by J.C. Bach (Op 5. Nos. 2, 3, and 4, all composed by 1766). Based on handwriting analysis of the autographs they are believed to date from 1771–72. Concerto No. 5, K. 175 from 1773 was
Twelve Concertos, Op. 7 (Vivaldi) Twelve Concertos, Op. 7 (Vivaldi) A set of twelve concertos was published by Estienne Roger in 1716-1717 under Antonio Vivaldi's name, as his Opus 7. They were in two volumes, each containing concertos numbered 1-6. Of the set, ten were for violin solo; the other two were for oboe solo. The authenticity of some of the works included has long been doubted by scholars. Three are now considered spurious (i.e. not in fact by Vivaldi) for stylistic reasons. They are: No. 1 in B-flat major for oboe, RV Anh. 143 (formerly RV 465); No. 7 in B-flat major for oboe,