OFFSET
1,1
COMMENTS
EXAMPLE
MATHEMATICA
S=0; a=0; Do[S=S+(Prime[2*k]-Prime[2*k-1])*(-1)^k; If[1-S==0, a++; Print[a, " ", 2*k]], {k, 1, 10^8, 1}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Manuel Valdivia, Jun 20 2007
STATUS
approved