Primality proof for n = 228728139988123081237499256083957678977837:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=250381879990652588256601.html>250381879990652588256601 is prime.</a>
<br>b^((n-1)/250381879990652588256601)-1 mod n = 205660410087993460753163052014875056903611, which is a unit, inverse 143056203127841678731160089489611361112086.
<p>(250381879990652588256601) divides n-1.
<p>(250381879990652588256601)^2 > n.
<p>n is prime by Pocklington's theorem.