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 A192320 #13 Feb 24 2019 04:13:08 %S A192320 1,1352,1353,1354,1355,1356,1357,1358,1359,1360,19657,19658,19659, %T A192320 19660,25522,31451,31452,31453,31454,31455,31456,31457,31458,31459, %U A192320 31460,31461,31462,31463,31464,31465,31466,31467,31468,34116,34117,34118,34119,34120,34121,34122 %N A192320 Numbers k for which there are no prime numbers in the range (k-4*sqrt(sqrt(k)), k]. %C A192320 a(69) = 492226 is probably the last term. Any further terms must be greater than 1.5 * 10^18. [_Charles R Greathouse IV_, Jun 27 2011] %H A192320 Charles R Greathouse IV, <a href="/A192320/b192320.txt">Table of n, a(n) for n = 1..69</a> %p A192320 isA192320 := proc(n) floor( n-4*root[4](n)) ; nextprime(%) > n ; end proc: %p A192320 for n from 1 do if isA192320(n) then printf("%d,\n",n) ;end if; end do: # _R. J. Mathar_, Jun 29 2011 %o A192320 (PARI) isA192320(n)=nextprime(floor(n+1-4*n^.25))>n \\ _Charles R Greathouse IV_, Jun 27 2011 %Y A192320 Subsequence of A192231. %Y A192320 Cf. A000040, A001223, A005669. %K A192320 nonn %O A192320 1,2 %A A192320 _Juri-Stepan Gerasimov_, Jun 27 2011 %E A192320 a(15) inserted, a(25) and a(34)-a(40) corrected by _Charles R Greathouse IV_, Jun 27 2011