# NIST B-283 Elliptic Curve

I'm new to Sage so forgive me if this is simple. I am trying to define the NIST B-283 elliptic curve as follows:

```
def B283_test():
order = 2**283
a = 1
b = 0x027B680AC8B8596DA5A4AF8A19A0303FCA97FD7645309FA2A581485AF6263E313B79A2F5
K.<x>= GF(2)[]
K.<a> = GF(order=order, name='a', modulus=x^283 + x^12 + x^7 + x^5 + 1 )
B283_curve = EllipticCurve(K, [1,a,0,0,b])
```

I get a fairly long traceback after the last line followed by:

```
OverflowError: long int too large to convert to int
```

Any help is appreciated.

Hmm. Looks like something is wrong with GF at large order. Does using `FF = sage.rings.finite_rings.finite_field_ext_pari.FiniteField_ext_pari; `K. = FF(order, 'a', modulus=x^283 + x^12 + x^7 + x^5 + 1 )[]` help any? [This changes the backend.]