2c:null 2d:["$","title",null,{"children":"The Recamán sequence | Kelley van Evert | Observable"}] 32:T7ee,md`Also, because I just had the enjoyment of writing PostScript for the very first time... If you save the below as recaman.eps, and then run ps2pdf recaman.eps on it, you get a nice pdf file with the same stuff :D Primary resource: http://www.cburch.com/csbsju/cs/portfolio/postscript.pdf. Also, don't kill yourself over the unpleasant interactivity of the gs command, while just trying to get to the bottom of this low-level stack-based language—use rlwrap gs -sDEVICE=bbox instead.

%!PS-Adobe-3.0 EPSF-3.0
%%BoundingBox: 0 0 595 842

% for coding: rlwrap gs -sDEVICE=bbox

/pagewidth  currentpagedevice /PageSize get 0 get def
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/N 200 def

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seq 0 0 put
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/mid {
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/pa {
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0 1 N {
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  m 0 lt had m 0 max get or {
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/cy pageheight 2 div def
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} for

showpage
%%EOF

`33:[] 30:{"id":"9900b7eb2ae79036","slug":"the-recaman-sequence","title":"The Recamán sequence","thumbnail":"38c4815085d80c48c5b86d7d010095d47178c87624ddfd5ef4f6f434c79ab36b","access_level":"public","create_time":"$D2018-06-20T20:26:11.906Z","update_time":"$D2018-09-13T11:35:00.256Z","view_time":null,"first_public_time":"$D2018-06-20T21:45:18.482Z","has_unpublished_edits":null,"fork":false,"stars":5,"starred":false,"owner":{"type":"team","id":"cdda271b76654961","login":"kelleyvanevert","name":"Kelley van Evert","avatar_url":"https://avatars-next.observableusercontent.com/86df2bc54dd099fad6826dfcf7ae3dd97c5e0cdcf0cf3e0ac85ecd13e1938db2","tier":"starter_2024"},"version":314,"publish_version":null,"role":null,"authored":false,"authors":[{"type":"individual","id":"a35690ff73833989","login":"kelleyvanevert","name":"Kelley van Evert","avatar_url":"https://avatars-next.observableusercontent.com/86df2bc54dd099fad6826dfcf7ae3dd97c5e0cdcf0cf3e0ac85ecd13e1938db2","tier":null}],"members":[{"type":"individual","id":"a35690ff73833989","login":"kelleyvanevert","name":"Kelley van Evert","avatar_url":"https://avatars-next.observableusercontent.com/86df2bc54dd099fad6826dfcf7ae3dd97c5e0cdcf0cf3e0ac85ecd13e1938db2","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":false,"trashed":false,"lapsed":null,"subscribed":null,"forks":4,"collection":{"id":"292860b4abec108d","slug":"visualizations","title":"Visualizations","owner":{"id":"cdda271b76654961","login":"kelleyvanevert","name":"Kelley van Evert"}},"type":"notebook","body":{"titling":"auto","title":"The Recamán sequence","cells":[{"id":0,"value":"md`# The Recamán sequence`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":260,"value":"md`See also:\n\n- The Slightly Spooky Recamán Sequence - Numberphile ([YouTube video](https://www.youtube.com/watch?v=FGC5TdIiT9U))\n- The On-Line Encyclopedia of Integer Sequences ([entry #A005132](https://oeis.org/A005132))\n\n*Note: The sliders below are restricted to reasonable maximums, but just for aesthetic reasons. Feel free to bump the numbers!* :D`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":8,"value":"html``","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":128,"value":"viewof len = slider({ min: 1, max: 500, step: 1, value: 200 })","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":241,"value":"viewof zoomout = slider({ min: 1, max: 10, value: 2.7 })","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":20,"value":"md`${list.join(', ')}…`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":310,"value":"md`## Bonus material: PostScript implementation`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":293,"value":"$32","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":291,"value":"md`## Implementation stuff`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":257,"value":"arcdata = {\n var d = 'M0 0';\n var max = 0;\n \n list.reduce((n0, n1, i) => {\n const w = Math.abs(n1 - n0);\n const s = (i + (n1-n0 > 0 ? 1 : 0)) % 2;\n d += `A 1 1 0 0 ${s} ${n1*10} 0`;\n return n1;\n });\n \n return { d, max };\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":139,"value":"list = seq(len)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":14,"value":"function seq (len) {\n \n while (cache.seq.length < len) {\n const k = cache.seq.length;\n const n = cache.seq[k-1];\n if (n-k < 0 || cache.had[n-k]) {\n cache.had[n+k] = true;\n cache.seq.push(n+k);\n } else {\n cache.had[n-k] = true;\n cache.seq.push(n-k);\n }\n }\n \n return cache.seq.slice(0, len);\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":44,"value":"viewof cache = {\n const view = md`**[Cache object]**`;\n view.value = { seq: [0], had: [true] };\n return view;\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":124,"value":"import { slider } from '@jashkenas/inputs'","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"}],"files":"$W33","stdlib":"1"}} 31:"$30:body"