[seqfan] Re: A154676

[Peter Pein]

zak seidov schrieb:
> Terms in A154676 are of the form 3708 n^2,
> and 1262 values of n<10^5 are in 
> http://zak08.livejournal.com/4070.html
> 
> In general A154676 is rather raw and needs some editing -
> sorry Vlad!
> 
> 
> 
> 
>       
> 
> 
> _______________________________________________
> 
> Seqfan Mailing list - http://list.seqfan.eu/
> 

Dear group,

could someone please check, if the following Mathematica-code gives correct
results. It seems slightly more efficient than that published in OEIS.
sorry for the unformatted output, but it is nearly 2:30am and I want to go to bed.
Have a nice day/night/time
Peter

Timing[lst = {};
   Do[If[PrimeQ[n - 1] &&
      PrimeQ[n + 1],
     If[IntegerQ[Sqrt[n*103]],
      AppendTo[lst, n]]],
    {n, 9!, 2*11!, 6}]; lst]
Out[1]=
{139.704731*Second, {2317500, 12047292, 26163648, 43250112, 47347452, 61704828}}
In[2]:=
Timing[lst = {}; Do[n = k^2/103;
     If[PrimeQ[n - 1] && PrimeQ[
        n + 1], AppendTo[lst, n]],
    {k, 103, 10300000, 103}]; lst]
Out[5]=
{1.096068*Second, {2317500, 12047292,
   26163648, 43250112, 47347452,
   61704828, 168228252, 333720000,
   351755712, 426127068, 513127872,
   840143808, 979638768, 998790588,
   1089276912, 1330434108, 1357220700,
   1388809152, 1694467008, 1927570428,
   1986835392, 2035992348, 2136108348,
   2858437872, 3070594800, 3241626300,
   3903322608, 5136799932, 5250898800,
   5303982528, 5812304832, 5830889328,
   6598593648, 7298860572, 7371874800,
   8232130800, 8566963200, 9779390208,
   10640610288, 11097673200,
   11136195612, 11174784768,
   11316849372, 11708859132,
   13428184572, 14027456700,
   15265246428, 15719995548,
   15919126272, 16445855088,
   18012040128, 18422979228,
   18821841372, 18955744668,
   19496104092, 19547152128,
   20095817472, 20407778928,
   20774770812, 21198194748,
   21429332928, 23603381532,
   24186972528, 24452865792,
   24720212592, 24950523888,
   25085365308, 25667372988,
   26572747932, 27211829148,
   31356568512, 32028669468,
   33039114300, 34879261212,
   37780307712, 38877059952,
   38949132348, 42663002112,
   43904503548, 45034494300,
   45215589312, 46152675072,
   46336002300, 46362221568,
   50872336128, 51423196608,
   52227213372, 54193639932,
   55764181872, 57707696700,
   58647689532, 59061324348,
   61936833852, 62361889308,
   64539905472, 64570848732,
   67702625532, 70293727728,
   72670603932, 74620518768,
   74886901488, 76326840252,
   80486889948, 81665915292,
   81700722288, 84226315248,
   84650985072, 88629806268,
   96293852928, 96596425728,
   97316938332, 100573062912,
   101075782428, 101812780800,
   108726810300, 110379506688,
   110500925148, 110703437568,
   111068427132, 112943310588,
   114256832508, 114503963292,
   118201087728, 118368630000,
   119839686300, 120980708352,
   124866191772, 125167618800,
   125771563008, 126723554928,
   126853650108, 127114040700,
   129732630300, 134334762588,
   135453002688, 139608039168,
   144936464832, 146377338012,
   149468742108, 150506388828,
   152640027648, 160055449200,
   160201651932, 160689476412,
   163927717308, 164865926592,
   165311275932, 169246231488,
   172720957500, 175006105200,
   176282120700, 189085310748,
   189244217088, 197599320000,
   199118057472, 202392073152,
   203379483888, 204314244732,
   206854343388, 209800434672,
   212655019932, 214681634748,
   215472358332, 219676043772,
   222079984668, 230129173872,
   247686720732, 251458854300,
   255628811772, 259398687168,
   260392075200, 278726281200,
   281885723388, 285974026992,
   286886536128, 289829445948,
   292655590848, 295826553792,
   296356708800, 297750623868,
   305643917628, 305711251200,
   309426018300, 310103840700,
   314186348700, 323400343068,
   331694556912, 343797012828,
   345584546928, 347233171932,
   360417158748, 363788264700,
   364817368188, 364890931200,
   376980824412, 395370231408,
   396596422512, 400671740700,
   401520171888, 405465532092,
   407795342652, 410756017500,
   413727401052, 417574729152,
   419307892848, 420649614108,
   421914368412, 423339486300,
   426515017500, 430261428672,
   439981820892, 443543429052,
   453493891548, 458840438208,
   464052377052, 477673830000,
   484516057788, 487402602300,
   489189750768, 489360125952,
   498260512512, 504815366592,
   515602086912, 516214414908,
   518228908272, 523590694812,
   525089880000, 529688927232,
   530398252800, 532795730652,
   548556213852, 562078455552,
   563997512412, 564454912752,
   564820966512, 571154071068,
   575118646128, 581509061532,
   588962438172, 606854428092,
   608373343548, 610845630300,
   636621362172, 649316367612,
   654922162800, 655316456688,
   663624037872, 685226667888,
   692605784412, 703697476608,
   719621797788, 721586070000,
   723242270448, 729990107388,
   743579779068, 755070793200,
   761965170300, 769959154800,
   786828289212, 803552674428,
   805081794300, 806502992832,
   809239589532, 820563254208,
   823544608572, 827860553712,
   835301460348, 841099437468,
   845237131632, 849946276800,
   876878533872, 887860858608,
   890272352700, 900297668592,
   907476401088, 913984920000,
   922621133808, 938716987068,
   944862804252, 949010702832,
   954833022972, 959957074800,
   966171920112, 975411503388,
   981676095228}}