A246131 Duplicate of A082180.

4, 9, 25, 49, 121, 125, 169, 289, 343, 361, 418, 529, 841, 961, 1331, 1369, 1681, 1849, 2197, 2209, 2809, 3481, 3721, 4489, 4913, 5041, 5329, 6241, 6859, 6889, 7921, 9409, 10201, 10609, 11449, 11881, 12167, 12769, 16129, 17161, 18769, 19321, 22201, 22801, 24389, 24649, 26569, 27173

Offset: 1

Author

Stanislav Sykora, Aug 16 2014

Keywords

• dead

Programs

Maple

select(n -> not isprime(n) and coeff(Power(1+x,2*n) mod n, x, n) = 2, [$4 .. 10000]); # Robert Israel, Sep 22 2014

PARI

a(file,nmax)={my(n=0,p=1);
  while(1,p++;if(((binomial(2*p,p)-2)%p)==0,
    if(!isprime(p),n++;write(file,n," ",p);if(n==nmax,break)));
  );}