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A275777
Primes p such that there are exactly p solutions to y^2 + x*y + y == x^3 + x^2 - 10*x - 10 (mod p).
0
7, 23, 31, 79, 167, 431, 479, 983, 1303, 1607, 1871, 2351, 4799, 6263, 6271, 9551, 10103, 10111, 11471, 11519, 12503, 12647, 12959, 14087, 17231, 17623, 21599, 23039, 25391, 25919, 25951, 28879, 29927, 33599, 35543, 43711, 48479, 48647, 49871, 56671, 57119, 62743, 71551, 71999, 79151, 81551, 82567, 91703, 96079, 97919
OFFSET
1,1
COMMENTS
Primes p = prime(n) for which A275742(n) = p.
Primes p for which A030184(p) == 0 (mod p).
Primes prime(A275745(n)) for which A275745(n) = 0.
PROG
(PARI)
{ N = 10^5 + 2;
default(seriesprecision, N);
V = Vec( eta(q) * eta(q^3) * eta(q^5) * eta(q^15) );
forprime(p=2, N, if( V[p]%p == 0, print1(p, ", ") ) );
} \\ Joerg Arndt, Sep 11 2016
(PARI) \\ Much slower than the above, but maybe useful for isolated values
is(n)=if(!isprime(n), return(0)); my(s, t, y='y); for(x=1, n, s+=#polrootsmod(y^2+x*y+y-x^3-x^2+10*x+10, n); if(s>n, return(0))); s==n \\ Charles R Greathouse IV, Sep 12 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 10 2016
EXTENSIONS
More terms from Joerg Arndt, Sep 11 2016
STATUS
approved