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 A048540 #13 Feb 16 2025 08:32:40 %S A048540 56,552,5550,5055752,5255556,552555542,2555555256,551555015556, %T A048540 5555555065506,515605555595550,5558455555057550,495553555055055552, %U A048540 555055556595557556,15975555555558555452,5525459555405553555552,59555925551555575555056,255555555455525595515520 %N A048540 Smallest oblong (promic) number containing exactly n 5's. %H A048540 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PronicNumber.html">Pronic Number</a> %Y A048540 Cf. A048539, A002378. %Y A048540 Cf. A048530, A048532, A048534, A048536, A048538, A048542, A048544, A048546, A048548. %K A048540 nonn,base %O A048540 1,1 %A A048540 _Patrick De Geest_, May 15 1999 %E A048540 a(14)-a(17) from _Giovanni Resta_, Oct 09 2019