Srinivasa Ramanujan

“ Squaring the circle
(Journal of the Indian Mathematical Society, v, 1913, 138)
Let be a circle with centre , of which a diameter is . Bisect at and let be the point of trisection of nearer . Draw perpendicular to and place the chord .
Join , and draw and parallel to . Place a chord , and draw the tangent . Join , and . Cut off . Draw parallel to , meeting at . ”

“ Each of these formulæ is the simplest of a large class.
↑ Proc. London Math. Soc., Ser. 1, Vol. xxv, 1894, pp. 318–343. ↑ Proc. Camb. Phil. Soc., Vol. xix, 1919, pp. 211–216. A short account of the history of the theorems is given by Mr Hardy in a note attached to this paper. [For Ramanujan's proofs see No. 26 of this volume: those of Rogers, and the note by Hardy referred to, are reproduced in the notes on No. 26 in the Appendix.] ”