Zhang Yitang
... that mathematician Zhang Yitang proposed a proof that there are infinitely many pairs of prime numbers with a prime gap of 70 million or less?
... that mathematician <b id="mwATU"><a class="mw-redirect" href="./Zhang_Yitang" id="mwATY" rel="mw:WikiLink" title="Zhang Yitang">Zhang Yitang</a></b> proposed a proof that there are infinitely many pairs of <a class="mw-redirect" href="./Prime_numbers" id="mwATc" rel="mw:WikiLink" title="Prime numbers">prime numbers</a> with a <a href="./Prime_gap" id="mwATg" rel="mw:WikiLink" title="Prime gap">prime gap</a> of 70 million or less?