%I #30 Nov 13 2018 03:17:44
%S 1,0,0,0,0,0,0,1,-7,54,-529,6192,-86580,1425517,-27298231,601580873,
%T -15116315767,429614643061,-13711655205088,488332318973593,
%U -19296579341940068,841693047573682615,-40338071854059455413,2115074863808199160560,-120866265222965259346027
%N Truncation of Bernoulli number: floor(|B_2n|) * sign(B_2n).
%D M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 810.
%H Robert Israel, <a href="/A014509/b014509.txt">Table of n, a(n) for n = 0..317</a>
%H M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%H <a href="/index/Be#Bernoulli">Index entries for sequences related to Bernoulli numbers.</a>
%F abs(a(n)) = 2*(2*n)!/(2*Pi)^(2*n)*(1-sum(k=2, m, 1/k^(2n))+O(1/m^(2n))). - _Benoit Cloitre_, Jan 29 2003
%p f:= proc(n) local b; b:= bernoulli(2*n);
%p floor(abs(b))*signum(b)
%p end proc:
%p map(f, [$0..30]); # _Robert Israel_, Nov 12 2018
%t Table[Sign@BernoulliB[2n] Floor@Abs@BernoulliB[2n], {n, 0, 20}] (* _Vladimir Reshetnikov_, Nov 12 2015 *)
%o (PARI) a(n) = my(b=bernfrac(2*n)); floor(abs(b))*sign(b); \\ _Michel Marcus_, Nov 13 2018
%Y Cf. A134825.
%K sign
%O 0,9
%A _Simon Plouffe_
%E Entry revised by _Franklin T. Adams-Watters_, Sep 14 2005