var f=0;
var vis=new Array();
var ops,extraspace;
var loaded=false,hasrun=false;;
var blinkCount=0;

function gen50()
{
  var upto=Math.floor(ops.length/50+1)*50;
  for(var i=vis.length;i<upto;i++)
    vis[i]=vis[i-1]+vis[i-2];
  hasrun=true;
}

function init(serwhich)
{
  if(serwhich=="lucas") //fibonacci is more difficult to spell, so its default-ish :)
    vis[0]=2,vis[1]=1;
  else
    vis[0]=0,vis[1]=1;
  ops=document.seriesForm.seriesSelect.options;
  extra=document.seriesForm.extraSpace;
}

function hit_button()
{
  if(!loaded)return false;
  return true;
}

function seriesForward()
{
  var upto=Math.floor(ops.length/50+1)*50;
  if(!hit_button())return false;
  while(upto>vis.length)
    gen50();
  for(var i=Math.floor(ops.length/50)*50;i<upto;i++)
    ops[i]=new Option("F("+(i+1)+")="+vis[i],null,false,false);
  return true;
}

function updateExtra(flag)
{
  if(!hasrun)return;
  if(flag)
    extra.value=ops[document.seriesForm.seriesSelect.selectedIndex].text;
  else
    extra.value=vis[document.seriesForm.seriesSelect.selectedIndex];
}