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A245014
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Least prime p such that 2n*4^n divides p + 4n^2 + 1.
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2
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3, 47, 347, 6079, 10139, 147311, 687931, 18874111, 37748411, 104857199, 276823579, 805305791, 29662117211, 30064770287, 64424508539, 2473901161471, 11098195491707, 7421703486191, 83562883709531, 527765581330879, 369435906930971, 27866022694353007, 19421773393033147
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OFFSET
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1,1
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COMMENTS
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All those terms such that 2n*4^n is equal to p + 4n^2 + 1 belong to A247024.
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LINKS
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FORMULA
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MATHEMATICA
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PROG
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(PARI) search(u)={ /* Slow, u must be a small integer. */
my(log2=log(2), q, t, t0, L1=List());
forprime(y=3, prime(10^u),
t=log(y+1)\log2;
while(t>t0,
q=4*t^2+y+1;
if(q%(t*(2^(2*t+1)))==0,
listput(L1, [t, y]);
t0=t;
break
,
t--
)));
L1
}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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