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  "body": "\n## Summary\n\nA Nörlund mean is a weighted average of the first terms of a sequence.\nIts weights are read backwards from a fixed sequence $p_0, p_1, p_2, \\dots$.\nIt defines a [[summability method|8X25Q4XYMN]] for sequences and, through partial sums, for series.\nWith all weights equal to $1$ it is the [[Cesàro mean|08R2V9GZF7]].\nThe method gives the usual limit to every convergent sequence exactly when $p_n$ is small compared with $p_0 + \\cdots + p_n$.\n\n## Explanations\n\n### L1 human\n\nTo average $s_0, \\dots, s_n$, the Nörlund mean gives the weight $p_0$ to the newest term $s_n$, the weight $p_1$ to $s_{n-1}$, and so on back to $p_n$ for $s_0$.\nThen it divides by the total weight.\nWith all weights equal it is the plain average.\nWeights that grow, such as $p_k = k + 1$, give more weight to the early terms of the sequence than the plain average does.\n",
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