p= 2: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p= 3: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p= 5: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p= 7: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p=11: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p=13: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p=17: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p=19: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
p=23: identity (1) and inverse True;  identity (2) True;  dF/dx = -1 True
all checks passed: True
