A = 
[[ 0  4  8  12 ]
[ 1  5  9  13 ]
[ 2  6  10  14 ]
[ 3  7  11  15 ]
]
A * x = 
24
28
32
36
x + 3x = 
4
4
4
4
Rsold is 4.8612e+13
pAp is 7.17245e+12
alpha is 6.7776
rsnew is 1.14625e+14
beta is 2.35797
	[STEP 459] residual = 9.162310e-11, ||x|| = 4.611171e+18, ||Ax - b||/||b|| = 1.336462e-12
5000 2 1.363271e+01