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 A056383 #10 May 01 2022 01:38:22
%S A056383 4,12,36,144,276,2124,2796,17760,44184,263004,419868,4278000,5593996,
%T A056383 44748804,134390724,539036160,1073758356,11453725416,15271054956,
%U A056383 137575549680,366528035564,1759219864020,3198580043436
%N A056383 Number of primitive (aperiodic) step shifted (decimated) sequences using a maximum of four different symbols.
%C A056383 See A056371 for an explanation of step shifts.
%D A056383 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 A056383 a(n) = Sum_{d|n} mu(d)*A056373(n/d).
%Y A056383 Cf. A056371, A056373.
%K A056383 nonn
%O A056383 1,1
%A A056383 _Marks R. Nester_