assertTrue("a non-neg", a.signum() >= 0);
BigInteger d = bi3.shiftRight(i);
assertTrue("c==d", c.equals(d));
c = c.shiftRight(1);
assertTrue(">>1 == /2", d.divide(two).equals(c));
assertTrue("c non-neg", c.signum() >= 0);
BigInteger f = E.shiftRight(i);
assertTrue("e==f", e.equals(f));
e = e.shiftRight(1);