Wednesday, August 27

What's on first?

A sequence that I'm currently attempting to extend: _, 91, 3854, 178086, 15469622, ... I've purposely left out the surprising first term.

Update: It is now a sequence in the OEIS.

Thursday, August 14

3329 is a prime balanced factorial

It may appear that the following Mathematica execution took just over an hour. In fact, it has taken me many weeks to be able to write it.

PrimeQ[3329!-7607]

True

DateString[]
NextPrime[3329!-7607]
DateString[]

Thu 14 Aug 2014 08:03:36

15015905410377990189612669728734416983623305863211194173984549864118912388614580813647063124137997910538082896578696443428869585291166176049551725545323619613247036490118670691372109371002766714784994640066135388162033055349621680311652435317541931644391114409952234156263908956775470653899105140924947400093330839839804546566886098947871580704800358703875896032243051062750594829590002645279915900517541293263702329765087215432815094241693060954235337839299957090323969065518806385266477265191459751472884324532373143637717234024009643597958281320271908345806890456895205227477366523110847604195929204092016300135023471997451803585110949233566181466735581417716495791896633922227547993640135431551957261121432488358580658859446738751102266955127145501461655564274215743921329774164182560773883535928923859928623997161281386873450899829022827207791609975077260505038324222182602036918649148183767166658704803906524987613581466322117907848171936943276831821376964038916006583422499204626298527081536155227098013942804257772011873945707081139954946428432796314243287864539867192889002088474220653113939262767909977843118614065596100525158318722437297244808511563252129894837185130204981906967470241971751053802841530211141663068662899843720213079867239111965654743779578216120280795733607532383934869566829618551012793251273877554076724502727685976158947950141105949105998628073350927074843754946373489924711282077736360892286369244279778940154812080055330072889475133632730945251644798926678264994198497000992008367717165132808168934785538022596478905028659057420416930567628708103579201145411632305879571078004102460653446380420754587421340701976673333458052068783677292030907456781166992041033853227604884045593985070171656690841917913386767434663058479118452860681284187827048282376831904398605646930051779380911926083051243238455870789275047464245298483271273587903898933743766245002439773172881419876698965849052031018467593963443053676700228214015169134222272062806393035636579926552904633221081761721750145823969767215320529290268701195654553582118809223232013064682937219611566989489148341352831033573418489718988963993993805180906729957424383324212800307148720599750226879494934765856972359660969425261751184149927233027360180134302879130697258875023207844329486751133716567025046003583124738472466899864638004330782854059337089289407398001945157970833338691320373787690787404398358801973738667634465389535587594564920681405752736888311729288272246605928966188557205785691991582812355266808177731327720417562922628147355990730291178024360246732978013628772377136439127156873731248096049600312044261976700965111637819443213683959071375872377007385562407517901374496065791398470908123128307172951685673964210294957748278324201913124374729962664204986302046111534390117942176782243884596262173616164570288711883087828143613585969830142617917940280965919462026407378592510796009217969597008566076229766572343218297868592522669735483527148243498594849361994602293289198078993889348199637296250334805245579058462482111308107426699517465259358792026716200140417484585776804584548583314915343968927754960036162463616241901324430769887203952214802182627959756314445982649524058545311882983999817506462539579403054799862166728589699965459595870991990477454573070360170460041592709595638178559759526185045600203679707267061923408643032494471030635862149983001990503501730690328336124960551908452915041292337581166837138829730178563626402194012313680409767407365529282594987058251861780629567748915228518807383123318556374750937396657975083779591327967943714152154031708084505572098305967040376312526574836658064336135383885522606380468729894197273977828913752002803865934866466084285902953586411476778976985089899167264960569336939422398346244930852202019983334892586386495084115977657343620760816749779886343559438100565067398263630336285623236852512608584848800379595081341663186071192321151990086732363604874257861770988096320978938181949641606264428409380443332636396632465601760606345384780029194243703020573863877365494050356895128710868090837593220445107522893493893198071574776656427848807860183960389256911014990675661921782737633755328058787385898107233714759984556019501248961899288732375240085754014381488919202762095781925676758015829258479348139284759396510731176651509365584251387608639622431879559280845192290535282131606838274408367717288414369423342336700514311757285373699847184742654453078953299536663552867918172295641752756713068488207022447052731729114606154499330438421861227323385195220807906861290851518445313496084054556664268969785557013526231921070169876121224039336072475628070498166383135566735553162710572353048006929601597922923678245925639836253997969994846638653526816282355145653404011655683832008197770593435993335541862133880574772037525994988372621711297467288289070241202104972328279553278766035547237128167481050565685242649901692721364948881010613778779764033462123023908305073504835838647614690148099964153342227610659482874003358958411030166863606333262359230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Thu 14 Aug 2014 09:12:03

Tuesday, August 5

A beautiful picture

I have suspected for years that the television picture supplied by the evil Canadian Rogers cable empire was sub-optimal at my Toronto house, owing (I thought) to a less-than-perfect infrastructure situation somewhere upstream. It all came to a head three years ago, as this lengthy complaint to an online Rogers employee attempts to explain. A senior technician did subsequently come to the house and declared my television — not their cabling — to be the problem. And alas, that television did indeed suffer from a defect (unbeknownst to me, as the set was borrowed from my daughter) that prevented proper reception on some channels. Rogers charged me $50 for the technician having to come to my house for no good reason, as it were. In light of the defect, I could not press the issue of sub-optimal reception.

Fast-forward to yesterday morning. I had lost my Teksavvy internet signal (which runs on Rogers' cable) and my television picture was somewhat more degraded than usual (so I knew it was an issue with the cable, not the modem). Rogers demands from Teksavvy a full accounting of the situation before they will issue a ticket for a technician to be sent and so I spent a full hour being interviewed by a Teksavvy employee, gathering modem and network details. Subsequently, Catherine found out from our immediate neighbours that they had lost their Rogers television signal altogether.


Early this morning a couple of Rogers subcontractor vehicles appeared and Catherine learned from their drivers that there were additional houses on the street without a Rogers signal. Unable to fix the problem on their own, they issued a Mayday to Rogers. The Rogers truck (pictured) appeared before ten. By noon I had my internet back — although it was off-again/on-again for several hours as they continued (I guess) to troubleshoot the line. Finally, they were done. I had my internet and when I turned on the television — I had a pristine picture the likes of which I had never seen. So yes, I did have a sub-optimal feed all these years!