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 A056395 #7 Aug 22 2017 20:53:10 %S A056395 1,2,4,11,18,117,161,1193,3530,27569,60333,863409,1636609,19122031, %T A056395 84580125,501915567,1492170609,23751685183,47340359591,637742820401, %U A056395 2546703019245,18317620839483,49923584451715 %N A056395 Number of step shifted (decimated) sequence structures using a maximum of six different symbols. %C A056395 See A056371 for an explanation of step shifts. Permuting the symbols will not change the structure. %D A056395 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 A056395 Use de Bruijn's generalization of Polya's enumeration theorem as discussed in reference. %Y A056395 Cf. A056375. %K A056395 nonn %O A056395 1,2 %A A056395 _Marks R. Nester_