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 A056418 #6 Aug 22 2017 20:53:11 %S A056418 0,0,0,0,6,150,400,4080,15480,127818,269340,3493680,5777190,57262450, %T A056418 210945182,1030388115,2493913170,32176448060,51785999300,562228325904, %U A056418 1805427491920,10438821843750,22865672706000 %N A056418 Number of step cyclic shifted sequences using exactly five different symbols. %C A056418 See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent. %D A056418 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 A056418 A056413(n)-5*A056412(n)+10*A056411(n)-10*A002729(n)+5. %Y A056418 Cf. A056413. %K A056418 nonn %O A056418 1,5 %A A056418 _Marks R. Nester_