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 A116086 #21 Jan 19 2025 00:36:31 %S A116086 8,25,32,121,2187,3125,32761,79507,97336,503284356 %N A116086 Perfect powers n with no primes between n and the next larger perfect power, which is in A116455. %C A116086 No other n<10^12. There is a conjecture that this sequence is finite. %C A116086 No other terms < 10^18. - _Jud McCranie_, Nov 03 2013 %C A116086 No other terms < 4.5*10^18. - _Giovanni Resta_, Apr 28 2014 %H A116086 <a href="http://listserv.nodak.edu/cgi-bin/wa.exe?A1=ind0603&L=nmbrthry">March 2006 NMBRTHRY Archives</a> %H A116086 PlanetMath, <a href="https://planetmath.org/redmondsunconjecture">Redmond-Sun conjecture</a> %e A116086 The prime-free ranges are (2^3,3^2), (5^2,3^3), (2^5,6^2), (11^2,5^3), (3^7,13^3), (5^5,56^2), (181^2,2^15), (43^3,282^2), (46^3,312^2), (22434^2,55^5). %t A116086 lim=10^12; lst={}; k=2; While[n=Floor[lim^(1/k)]; n>=2, lst=Join[lst,Range[2,n]^k]; k++ ]; lst=Union[lst]; PrimeFree[n1_,n2_] := Module[{n=n1+1}, While[n<n2&&!PrimeQ[n], n++ ]; n ==n2]; lst2={}; Do[If[PrimeFree[lst[[i]],lst[[i+1]]], AppendTo[lst2,lst[[i]]]], {i,Length[lst]-1}]; lst2 %Y A116086 Cf. A001597 (perfect powers), A116455. %Y A116086 Cf. A068435 (for prime powers). %K A116086 hard,nonn %O A116086 1,1 %A A116086 _T. D. Noe_, Mar 28 2006