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A246131 Duplicate of A082180. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..48.

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

PROG

(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)));

  ); }

CROSSREFS

Sequence in context: A247136 A158145 A082180 * A068999 A179707 A247078

Adjacent sequences:  A246128 A246129 A246130 * A246132 A246133 A246134

KEYWORD

dead

AUTHOR

Stanislav Sykora, Aug 16 2014

STATUS

approved

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Last modified August 20 12:41 EDT 2018. Contains 313917 sequences. (Running on oeis4.)