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 A056443 #6 Aug 22 2017 20:53:12 %S A056443 1,1,2,5,7,33,35,212,449,2991,5651,74919,126757,1370979,5653844, %T A056443 31440622,87796361,1319721998,2491714133,31893714060,121274777190, %U A056443 832622957033,2170594048581,34308978905916 %N A056443 Number of primitive (period n) step cyclic shifted sequence structures using a maximum of six different symbols. %C A056443 See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent. Permuting the symbols will not change the structure. %D A056443 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 A056443 sum mu(d)*A056433(n/d) where d|n. %Y A056443 Cf. A056423. %K A056443 nonn %O A056443 1,3 %A A056443 _Marks R. Nester_