Visualization of a specialized "look and say" sequence

<!DOCTYPE html>
<meta charset="utf-8">
<style>

body {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

.dot {
  stroke: #000;
}

.h1 {
  font-size: 30;
  font-family: "Futura";
  color: red;
  text-align: center;
}

</style>
<body>
<center><h1>Look and Say 25</h1></center>
<script src="https://d3js.org/d3.v3.min.js"></script>
<script>

var margin = {top: 20, right: 20, bottom: 30, left: 40},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var x = d3.scale.linear()
    .range([0, width]);

var y = d3.scale.linear()
    .range([height, 0]);

var color = d3.scale.category10();

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left");

var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

d3.tsv("data3.tsv", function(error, data) {
  data.forEach(function(d) {
    d.Xco = +d.Xco;
    d.Yco = +d.Yco;
  });

x.domain(d3.extent(data, function(d) { return d.Xco; })).nice();
  y.domain(d3.extent(data, function(d) { return d.Yco; })).nice();

svg.selectAll(".dot")
      .data(data)
    .enter().append("circle")
      .attr("class", "dot")
      .attr("r", 3.5)
      .attr("cx", function(d) { return x(d.Xco); })
      .attr("cy", function(d) { return y(d.Yco); });

});

</script>

Modified http://d3js.org/d3.v3.min.js to a secure url

https://d3js.org/d3.v3.min.js