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 A247834 #26 Dec 23 2024 14:53:44 %S A247834 8,45,125,343,325,833,1331,1573,2197,2057,3211,3289,4913,4901,6859, %T A247834 6647,8303,10051,10469,11191,12167,15341,16399,17081,18259,22103, %U A247834 24389,26071,29791,27347,31117,35557,36163,36859,39401,42439,50653,50933,52111,56129,56699 %N A247834 Maximal non-semiprime number which is a "preprime" of the n-th kind (defined in comment in A247395). %C A247834 Conjecture: the sequence contains all cubes of primes, except for 3^3 (cf. A030078). %C A247834 Prime(n)^3 is in the sequence iff the interval [prime(n)^(3/2), prime(n)*sqrt(prime(n+1))] contains a prime. %C A247834 A simple algorithm for finding the position k=k(n) for which a(k) = prime(n)^3 is given in A247835 (see formula and example there). %C A247834 Conjecture: every term has the form a(n)= p*q*r, where p<=q<=r are primes. %H A247834 Vladimir Shevelev , <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2014-September/013643.html">A classification of the positive integers over primes</a> %Y A247834 Cf. A030078, A156759, A247393, A247394, A247395, A247396, A247509, A247510, A247511, A247606, A247835, A247867. %K A247834 nonn %O A247834 1,1 %A A247834 _Vladimir Shevelev_, Sep 24 2014 %E A247834 More terms from _Peter J. C. Moses_, Sep 24 2014