donut with padding and centroid dots

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
   var data = [1, 1, 2, 3, 5, 8, 13, 21];

var width = 960,
    height = 500,
    radius = height / 2 - 10;

var arc = d3.arc()
    .innerRadius(radius - 40)
    .outerRadius(radius);

var pie = d3.pie()
    .padAngle(.01);

var dot = d3.symbol();
var arcs = pie(data);

var color = d3.scaleOrdinal(d3.schemeCategory10);
    
var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height)
  	.append("g")
    .attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");

svg.selectAll("path")
    .data(arcs)
  	.enter().append("path")
    .style("fill", function(d, i) { return color(i); })
    .attr("d", arc);

arcs.forEach(function(d, i) {
  	var c = arc.centroid(d);
  	d3.select(d)
      .append("path")
    	.attr("d", dot)
			.attr("transform", function(d, i) {
  			var c = arc.centroid(d1);
  			return "translate(" + c[0] + "," + c[1] + ")";
			});
});
    
  </script>
</body>

https://d3js.org/d3.v4.min.js