# Terms of OEIS sequence A254718 and their prime factors # # Note: the values listed below for a(72), a(73), a(79), and a(84) # have not yet been confirmed; if any one of those values is not # actually a semiprime, then it is not the correct value for that # term of the sequence, and all subsequent values are probably # incorrect as well. See notes below. # # Jon E. Schoenfield, Feb 21 2015 # 1 4 = 2 * 2 2 14 = 2 * 7 3 141 = 3 * 47 4 1141 = 7 * 163 5 11141 = 13 * 857 6 111413 = 43 * 2591 7 1111413 = 3 * 370471 8 11114137 = 47 * 236471 9 111114137 = 31 * 3584327 10 1111141373 = 1051 * 1057223 11 11111141373 = 3 * 3703713791 12 111111413737 = 349 * 318370813 13 1111114137373 = 101 * 11001130073 14 11111141373734 = 2 * 5555570686867 15 1111114137373402 = 2 * 555557068686701 16 11111141373734023 = 17 * 653596551396119 17 111111413737340234 = 2 * 55555706868670117 18 11111114137373402349 = 3 * 3703704712457800783 19 111111114137373402349 = 11 * 10101010376124854759 20 1111111141373734023499 = 2608829107 * 425904149257 21 111111114137373402349901 = 1006279 * 110417800766361419 22 1111111141373734023499013 = 59 * 18832392226673458025407 23 11111111413737340234990133 = 11167787 * 994925083522576159 24 211111111413737340234990133 = 3583842713887 * 58906355068459 25 3211111111413737340234990133 = 191 * 16812100059757787121649163 26 32111111114137373402349901333 = 691729697 * 46421472510724623989 27 321111111141373734023499013333 = 1553 * 206768262164438978765936261 28 4321111111141373734023499013333 = 3513747529 * 1229772792574868498477 29 43211111111413737340234990133339 = 4397453 * 9826395213641564182774663 30 243211111111413737340234990133339 = 2776063 * 87610083456828514821254053 31 2432111111114137373402349901333394 = 2 * 1216055555557068686701174950666697 32 243211111111413737340234990133339406 = 2 * 121605555555706868670117495066669703 33 12432111111114137373402349901333394067 = 287013354306967 * 43315444820096159091301 34 712432111111114137373402349901333394067 = 126180635433539 * 5646128731744749367773553 35 17124321111111141373734023499013333940677 = 6246085484767 * 2741608508701019828623328731 36 1171243211111111413737340234990133339406773 = 28102621 * 41677365648958914321099808981878713 37 21171243211111111413737340234990133339406773 = 17 * 1245367247712418318455137660881772549376869 38 2117124321111111141373734023499013333940677301 = 10729998680330913592093 * 197308907874517925096057 39 72117124321111111141373734023499013333940677301 = 3 * 24039041440370370380457911341166337777980225767 40 172117124321111111141373734023499013333940677301 = 20929019 * 8223850545556440612021697434719659499279 41 1721171243211111111413737340234990133339406773019 = 872825116321 * 1971954302215695842100972464363156539 42 17211712432111111114137373402349901333394067730194 = 2 * 8605856216055555557068686701174950666697033865097 43 172117124321111111141373734023499013333940677301943 = 139976955341 * 1229610430529896541403397533579298495123 44 11721171243211111111413737340234990133339406773019437 = 158161589936295524753 * 74108835450706935767194129867229 45 1172117124321111111141373734023499013333940677301943713 = 648709252755787 * 1806845084052417808896379106199538738499 46 117211712432111111114137373402349901333394067730194371327 = 1889 * 62049609545850244104890086502038063172786695463310943 47 2117211712432111111114137373402349901333394067730194371327 = 7 * 302458816061730158730591053343192843047627723961456338761 48 92117211712432111111114137373402349901333394067730194371327 = 2235364553 * 41209033036157351606314989004570812795443569005959 49 1392117211712432111111114137373402349901333394067730194371327 = 13173192853087049 * 105678040793747190982391005169138109124770823 50 13921172117124321111111141373734023499013333940677301943713278 = 2 * 6960586058562160555555570686867011749506666970338650971856639 51 1392117211712432111111114137373402349901333394067730194371327809 = 53 * 26266362485140228511530455422139666979270441397504343290025053 52 13921172117124321111111141373734023499013333940677301943713278099 = 1433484597007 * 9711420789724984513093492613330374732111628903364157 53 1139211721171243211111111413737340234990133339406773019437132780993 = 13789 * 82617428469884923570317747025697311987100829603798173865917237 54 21139211721171243211111111413737340234990133339406773019437132780993 = 9661 * 2188097683590854281245327752172377624986040093096653868071331413 55 121139211721171243211111111413737340234990133339406773019437132780993 = 13 * 9318400901628557170085470108749026171922317949185136386110548675461 56 12113921172117124321111111141373734023499013333940677301943713278099329 = 17837 * 679145661945233185014919052608271235269328549304293171606419985317 57 1112113921172117124321111111141373734023499013333940677301943713278099329 = 3 * 370704640390705708107037037047124578007833004444646892433981237759366443 58 11112113921172117124321111111141373734023499013333940677301943713278099329 = 103 * 107884601176428321595350593312052172174985427313921754148562560323088343 59 411112113921172117124321111111141373734023499013333940677301943713278099329 = 83 * 4953157999050266471377362784471582816072572277269083622618095707388892763 60 4111121139211721171243211111111413737340234990133339406773019437132780993293 = 3042959 * 1351027450324411591231827675335557836086596957150372189297660414462627 61 154111121139211721171243211111111413737340234990133339406773019437132780993293 = 11 * 14010101921746520106476655555555583067030930453648485400615729039739343726663 62 12154111121139211721171243211111111413737340234990133339406773019437132780993293 = 2088727067762284899900886667 * 5818908228235041991189291386380584145195587964839879 63 1112154111121139211721171243211111111413737340234990133339406773019437132780993293 = 9929 * 112010686989741082860426149986011794885057643290864148790352177764068600340517 64 11121541111211392117211712432111111114137373402349901333394067730194371327809932937 = 29 * 383501417627979038524541808003831417728874944908617287358416128627392114752066653 65 811121541111211392117211712432111111114137373402349901333394067730194371327809932937 = 225779565491 * 3592537435118521516657265451607162828819430245832963893917542076124919507 66 12811121541111211392117211712432111111114137373402349901333394067730194371327809932937 = 16610181153542355792361036097776423 * 771281265549536690848086263904943236635981212698319 67 812811121541111211392117211712432111111114137373402349901333394067730194371327809932937 = 3 * 270937040513703737130705737237477370370371379124467449967111131355910064790442603310979 68 8128111215411112113921172117124321111111141373734023499013333940677301943713278099329371 = 12669072835392204001480284763268853471103 * 641571117398938322106751939105237874427514475557 69 158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371 = 38638647266196531710543 * 4092485695112606142754809693106145532208978284095591450861888626997 70 11581281112154111121139211721171243211111111413737340234990133339406773019437132780993293719 = 463 * 25013566116963522939825511276827739116870651001592527505378257752498429847596399095017913 71 511581281112154111121139211721171243211111111413737340234990133339406773019437132780993293719 = 7 * 73083040158879158731591315960167320458730158773391048604998590477058110431348161825856184817 # All the values above are correct. # # Each of the values below is correct if two conditions are met: # (1) the value is a semiprime, and # (2) all the values preceding it are correct. # # E.g., if the values listed below for n=72 and n=73 are both semiprimes, then # - they are the correct values for a(72) and a(73), # - the values listed for n=74..78 are the correct values for a(74)..a(78) # - the values listed for n=79..83 are correct _IF_ the value listed for n=79 is a semprime # - the value listed for n=84 is correct _IF_ both it and the value listed for n=79 are semiprimes. # 72 1511581281112154111121139211721171243211111111413737340234990133339406773019437132780993293719 = ? 73 151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957 = ? 74 9151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957 = 2351 * 3892453478567084394347985504539394778528758447954646420256698857224134698979984565409655180507 75 59151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957 = 752291451731 * 78627981205962369961258035723035875640678902275343145127336639008610583774941245442647 76 1559151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957 = 4447 * 350607411317317565867126627821266498116555230742329969357774566902031468557972103376046345700331 77 155915115812811121541111211392117211712432111111114137373402349901333394067730194371327809932937195751 = 613 * 254347660379789757815842106675558257279660866412910501424799918272974541709184656396945856334318427 78 1155915115812811121541111211392117211712432111111114137373402349901333394067730194371327809932937195751 = 10193295436421 * 113399550029982071342613517412905574581601763378170744799277145795937638286621760253732731 79 11559151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957513 = ? 80 511559151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957513 = 1657 * 308726102086981358609179910750706802726085890833500990569543767953538523802460652953357440011665281809 81 28511559151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957513 = 56437 * 505192677696513424016432679130958788952586500365205647737720538361341200523427490864923955527390353349 82 2285115591511581281112154111121139211721171243211111111413737340234990133339406773019437132780993293719575139 = 43 * 53142223058408867002608235142352074691190028911886304916598542796162561240451320302777607739092867295804073 83 12285115591511581281112154111121139211721171243211111111413737340234990133339406773019437132780993293719575139 = 97 * 126650676201150322485692310423929270223929600445475372282615848868401960137519657453808630234855600966181187 84 1228511559151158128111215411112113921172117124321111111141373734023499013333940677301943713278099329371957513909 = ?