39 lines
1.4 KiB
C
39 lines
1.4 KiB
C
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/*=============================================================================
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This file is part of FLINT.
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FLINT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License,or
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(at your option) any later version.
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FLINT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with FLINT; if not,write to the Free Software
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Foundation,Inc.,51 Franklin St,Fifth Floor,Boston,MA 02110-1301 USA
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=============================================================================*/
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/******************************************************************************
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Copyright (C) 2009 William Hart
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Copyright (C) 2010 Fredrik Johansson
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******************************************************************************/
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#include <gmp.h>
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#include "flint.h"
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#include "ulong_extras.h"
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void n_prime_pi_bounds(ulong *lo, ulong *hi, mp_limb_t n)
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{
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int lg2 = FLINT_BIT_COUNT(n);
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*lo = (ulong)(((double)n)/((double)lg2*0.6931472));
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*hi = (ulong)(((double)n)/((double)(lg2-1)*0.5522821));
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}
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