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%I #3 Mar 30 2012 18:35:47
%S 22,38,200,302,468,560,1186,1208,2006,2026,2106,23698,23716,25968,
%T 25990,26706,48316,311888,311914,311938,313866,331540,332002,377102,
%U 377634,377670,377748,378428,378452,378996,379026,379090,387618,388140,389398
%N Numbers n such that 1 + S(n) = 0, where S(n) = (S(n-1) + A000040(n))*(-1)^n; S(0)=0, n=>1.
%C The terms are equal to A130642 for n/2 even (70 terms) and to A130643 for n/2 odd (91 terms).
%e S(21)=(..((((0+2)*-1)+3)*1)+5)*-1)+7)*1)+11)*- 1)+13)*1)+...+71)*1)+73)*-1 = -80, 1 + S(22) =1 + (-80 + 79)*1 = 0, hence 22 is a term.
%e S(37)=(..((((0+2)*-1)+3)*1)+5)*-1)+7)*1)+11)*- 1)+13)*1)+...+151)*1)+157)*-1 = -164, 1 + S(38) =1 + (-164 + 163)*1 = 0, hence 38 is a term.
%t S=0;a=0; Do[S=(S+Prime[n])*(-1)^n; If[1+S==0,a++; Print[a," ",n]], {n, 1, 10^8, 1}]
%Y Cf. A130642, A130643, A008347, A066033, A000040.
%K nonn
%O 1,1
%A _Manuel Valdivia_, Sep 26 2007
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