21. If our gender is no longer news, then this is the first proof of true equality. 22. This was the first proof , indirect though it was, of the existence of gravity waves. 23. The first proof of the theorem is due to Constantin Carath�odory, who published it in 1912. 24. The Jordan curve theorem is named after the mathematician Camille Jordan, who found its first proof . 25. And remarked that the proof followed Gauss's first proof of the Law of Quadratic Reciprocity. 26. If this is confirmed, it would be the first proof of Iran's involvement in Afghanistan. 27. The first proof was given by, where the formulation of the problem was attributed to Stanislaw Ulam. 28. The first proof of the four colour theorem was a proof by exhaustion with 1, 936 cases. 29. The first proof that such a representation exists was given by Leonhard Euler in 1747 and was complicated. 30. :: The first proof was when the suns spectra was first analysed and absorption lines were seen.
