42 lines
1.4 KiB
C
42 lines
1.4 KiB
C
/*=============================================================================
|
|
|
|
This file is part of FLINT.
|
|
|
|
FLINT is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
FLINT is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with FLINT; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
=============================================================================*/
|
|
/******************************************************************************
|
|
|
|
Copyright (C) 2011 Fredrik Johansson
|
|
|
|
******************************************************************************/
|
|
|
|
#include <math.h>
|
|
#include "arith.h"
|
|
|
|
double arith_bernoulli_number_size(ulong n)
|
|
{
|
|
double x;
|
|
|
|
/* |B_n| < 2 */
|
|
if (n <= 14)
|
|
return 1.0;
|
|
|
|
x = 2 + (n + 1) * log(n + 1) * 1.44269504088897; /* 1/log(2) */
|
|
x -= n * 4.0941911703612822; /* log2(2*pi*e) */
|
|
|
|
return x + 2;
|
|
}
|