(kill (all), 0);
0;

(zeta%pi : true, 0);
0$

(chk(x) := zeta(1-x) - 2 * cos(x * %pi /2) * gamma(x) * zeta(x) / (2 * %pi)^x, 0);
0$

every(lambda([e], is(equal(e,0))), makelist(chk(k),k,2,21));
true$

every(lambda([e], is(equal(e,0))), makelist(zeta(-k) + bern(k+1)/(k+1),k,1,21));
true$

zeta(-1);
-1/12$

zeta(0);
-1/2$

zeta(0.0);
-0.5$

zeta(0.0b0);
-0.5b0$

errcatch(zeta(1)); /* zeta(1) is undefined */
[];

errcatch(zeta(1.0));
[];

errcatch(zeta(1.0b0));
[];

/* Check the limit */
limit(zeta(x),x,1,plus);
inf;

limit(zeta(x),x,1,minus);
minf;

limit(zeta(x),x,1);
infinity;

zeta(2);
%pi^2 /6$

zeta(4);
%pi^4 / 90$

zeta(6);
%pi^6 / 945$

zeta(8);
%pi^8/9450$

zeta(10);
%pi^10/93555$

/* bfloat(zeta(5)) should not return a rational! */
bfloat(zeta(5));
1.03692775514337b0;

(remfunction(chk),0);
0$
