A068487 Smallest prime equal to n^2 + m^2 with n

5, 13, 73, 41, 61, 157, 113, 233, 181, 269, 317, 313, 569, 421, 709, 617, 613, 853, 761, 929, 1117, 1013, 1429, 1201, 1301, 1637, 1753, 1873, 1741, 1861, 2897, 2113, 2689, 2381, 2521, 3697, 2969, 3469, 3121, 3449, 3617, 3613, 4153, 4337, 4729, 4517, 4513

Offset: 1

Author

Lekraj Beedassy, Mar 11 2002

Keywords

• nonn

Comments

All terms are congruent to 1 (mod 4). - Carmine Suriano, Mar 30 2011

Links

• Carmine Suriano, Table of n, a(n) for n = 1..872

Crossrefs

Cf. A089489 (values of m).

Programs

Maple

for n from 1 to 100 do m := n+1:while(not isprime(n^2+m^2)) do m := m+1; end do:a[n] := n^2+m^2:end do:q := seq(a[i],i=1..100);

Mathematica

Table[k = n + 1; While[p = n^2 + k^2; ! PrimeQ[p], k++]; p, {n, 100}] (* T. D. Noe, Mar 30 2011 *)

Extensions

More terms from Sascha Kurz, Mar 17 2002