{
  "aliases": null,
  "backlinks": null,
  "body": "\n## Definition\n\nLet $R$ be a commutative ring, and let $E$ be a linear recurrence with constant coefficients over $R$ of order $d$.\nThe space of solutions of $E$ is the set of all [[solutions|0ZV2YKKZ58]] of $E$.\nIt is a submodule of the $R$-module $R^{\\mathbb{N}}$ of all sequences in $R$, with termwise addition and scalar multiplication.\n\n## Remarks\n\nThe map $u \\mapsto (u_0, \\dots, u_{d-1})$ is an isomorphism of $R$-modules from the space of solutions to $R^d$. Over a field, the space of solutions has dimension $d$.\nFor the Fibonacci recurrence over $\\mathbb{R}$, the sequences $\\varphi^n$ and $\\psi^n$ form a basis, with $\\varphi$ and $\\psi$ the roots of $X^2 - X - 1$.\n\n## Explanations\n\n### L1 human\n\nIf two sequences solve the same linear recurrence, then so does their sum, and so does any multiple of one of them.\nSo the solutions form a vector space, and the first $d$ terms are coordinates on it.\n",
  "commit": "6ac761d40018146541484a9e8b9eafd6ecc303dc",
  "front": {
    "defines": "099GXMHV40",
    "kind": "definition",
    "msc": [
      "39A06"
    ],
    "name": "Space of solutions of a linear recurrence",
    "sources": [
      {
        "locator": "General solution",
        "url": "https://en.wikipedia.org/wiki/Linear_recurrence_with_constant_coefficients"
      }
    ],
    "tag": "05BDYVQQ0T",
    "uses": [
      "0ZV2YKKZ58"
    ]
  },
  "kind": "definition",
  "link": "https://math2.tamnd.com/node/05BDYVQQ0T/",
  "links": [
    {
      "field": "defines",
      "target": "099GXMHV40"
    },
    {
      "field": "uses",
      "target": "0ZV2YKKZ58"
    }
  ],
  "markdown": "https://math2.tamnd.com/node/05BDYVQQ0T.md",
  "msc": [
    "39A06"
  ],
  "name": "Space of solutions of a linear recurrence",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/05B/05BDYVQQ0T.md",
  "status": null,
  "tag": "05BDYVQQ0T",
  "uri": "m2://05BDYVQQ0T",
  "url": "https://math2.tamnd.com/wiki/space-of-solutions-of-a-linear-recurrence-definition/",
  "writing": {
    "tag": "05BDYVQQ0T",
    "kind": "definition",
    "level": "W0",
    "next": [
      {
        "what": "an inventory row",
        "note": "the row of the inventory that the node accounts for",
        "have": 0,
        "want": 1
      }
    ]
  }
}
