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 A056465 #10 Sep 29 2019 11:10:11
%S A056465 0,0,0,0,0,0,24,24,240,240,1560,1560,8400,8376,40824,40800,186480,
%T A056465 186240,818520,818280,3497976,3496440,14676024,14674440,60780720,
%U A056465 60772320,249401640,249393480,1016542800,1016501736,4123173624,4123132800,16664093400,16663908480
%N A056465 Number of primitive (aperiodic) palindromes using exactly four different symbols.
%D A056465 M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]
%H A056465 Andrew Howroyd, <a href="/A056465/b056465.txt">Table of n, a(n) for n = 1..200</a>
%F A056465 a(n) = Sum_{d|n} mu(d)*A056455(n/d).
%Y A056465 Column 4 of A327873.
%Y A056465 Cf. A056455, A056460.
%K A056465 nonn
%O A056465 1,7
%A A056465 _Marks R. Nester_
%E A056465 Terms a(31) and beyond from _Andrew Howroyd_, Sep 28 2019