This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A245304 #21 Sep 08 2022 08:46:08 %S A245304 4,10,100,1480,16060,19420,21010,22270,43780,55330,144160,165700, %T A245304 166840,195730,201820,225340,247600,268810,326140,347980,361210, %U A245304 397750,465160,518800,536440,633460,633790,661090,768190,795790,829720,857950,876010,958540 %N A245304 Numbers m such that m+1, m+3, m+7, m+9 and m+13 are all primes. %D A245304 W. SierpiĆski, 250 Problems in Elementary Number Theory. New York: American Elsevier, 1970. Problem #82, variant. %H A245304 Reinhard Zumkeller and Jens Kruse Andersen, <a href="/A245304/b245304.txt">Table of n, a(n) for n = 1..1000</a> (first 120 terms from Zumkeller) %F A245304 a(n) = A022006(n)-1. - _Jens Kruse Andersen_, Jul 18 2014 %t A245304 Select[Range[10^6],AllTrue[#+{1,3,7,9,13},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, May 07 2015 *) %o A245304 (Haskell) %o A245304 a245304 n = a245304_list !! (n-1) %o A245304 a245304_list = map (pred . head) $ filter (all (== 1) . map a010051') $ %o A245304 iterate (zipWith (+) [1, 1, 1, 1, 1]) [1, 3, 7, 9, 13] %o A245304 (PARI) forprime(p=2, 10^7, m=p-1; if(isprime(m+3)&&isprime(m+7)&&isprime(m+9)&&isprime(m+13), print1(m", "))) \\ _Jens Kruse Andersen_, Jul 18 2014 %o A245304 (Magma) [n: n in [0..10^6] | IsPrime(n+1) and IsPrime(n+3) and IsPrime(n+7) and IsPrime(n+9) and IsPrime(n+13)]; // _Vincenzo Librandi_, Jun 15 2015 %Y A245304 Cf. A010051, A022006, A245305, A007811, subsequence of A125855. %K A245304 nonn %O A245304 1,1 %A A245304 _Reinhard Zumkeller_, Jul 18 2014