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 A056462 #20 Apr 25 2020 01:19:36
%S A056462 6,0,30,30,210,180,1290,1260,7740,7560,46650,46410,279930,278640,
%T A056462 1679370,1678320,10077690,10069740,60466170,60458370,362795730,
%U A056462 362750400,2176782330,2176734420,13060693800,13060414080,78364156320,78363884130,470184984570,470183297220
%N A056462 Number of primitive (aperiodic) palindromes using a maximum of six different symbols.
%D A056462 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]
%F A056462 a(n) = Sum_{d|n} mu(d)*A056452(n/d).
%o A056462 (PARI) a(n) = sumdiv(n, d, moebius(d)*6^((1 + n/d)\2));
%o A056462 for(n=1, 32, print1(a(n), ", ")); \\ _Petros Hadjicostas_, Apr 24 2020
%Y A056462 Cf. A056391, A056452.
%Y A056462 Column 6 of A284823.
%K A056462 nonn
%O A056462 1,1
%A A056462 _Marks R. Nester_
%E A056462 More terms from _Petros Hadjicostas_, Apr 24 2020