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 A261791 #27 Feb 16 2025 08:33:27
%S A261791 19,157,532,1263,2467,4263,6770,10106,14389,19739,26272,34109,43367,
%T A261791 54164,66619,80851,96978,115119,135391,157913,182804,210183,240166,
%U A261791 272874,308425,346936,388526,433315,481419,532958
%N A261791 The integer part of the surface area of the 4-dimensional sphere of radius n.
%C A261791 2*Pi^2*n^3 - surface area of the 4-dimensional sphere of radius n.
%H A261791 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Hypersphere.html">Hypersphere</a>
%H A261791 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/FloorFunction.html">Floor Function</a>
%H A261791 Wikipedia, <a href="https://en.wikipedia.org/wiki/N-sphere">N-sphere</a>
%F A261791 a(n) = floor(2*Pi^2*n^3).
%F A261791 a(n) = floor(2*Pi^2*A000578(n)).
%t A261791 Table[Floor[2 Pi^2 n^3], {n, 1, 30}]
%o A261791 (PARI) a(n) = floor(2*Pi^2*n^3) \\ _Charles R Greathouse IV_, Sep 18 2015
%Y A261791 Cf. A038130, A000578, A164102 (2*Pi^2), A210519, A066644.
%K A261791 nonn
%O A261791 1,1
%A A261791 _Ilya Gutkovskiy_, Sep 01 2015