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 A174074 #14 Feb 04 2024 18:19:41 %S A174074 1,1,1,2,6,22,109,657,4625,37186,336336,3379058,37328103,449669577, %T A174074 5866178493,82387080624,1239364493118,19881771085788,338797668091565, %U A174074 6111688544942463,116354993433563797,2331395107113471188,49042688584011866880,1080639600739277669092,24891049832682424745839 %N A174074 Number of circular permutations of length n without consecutive triples i,i+2,i+4. %C A174074 Circular permutations are permutations whose indices are from the ring of integers modulo n. %D A174074 Wayne M. Dymacek, Isaac Lambert and Kyle Parsons, Arithmetic Progressions in Permutations, http://math.ku.edu/~ilambert/CN.pdf, 2012. %H A174074 Max Alekseyev, <a href="/A174074/b174074.txt">Table of n, a(n) for n = 0..100</a> %H A174074 Kyle Parsons, <a href="http://hdl.handle.net/11021/23093">Arithmetic Progressions in Permutations</a>, thesis, 2011. See Table 3, p. 9. %e A174074 Since a(5)=22, there are (5-1)!-22=2 circular permutations with consecutive triples i,i+2,i+4 in all circular permutations of length 5. They are exactly (0,2,4,1,3) and (0,2,4,3,1). %Y A174074 Column 1 of A216719. %Y A174074 Cf. A165961, A174072, A174073, A174075. %K A174074 nonn %O A174074 0,4 %A A174074 _Isaac Lambert_, Mar 06 2010 %E A174074 a(10)-a(15) from _Donovan Johnson_, Sep 24 2010 %E A174074 a(0)-a(2) prepended and terms a(16) onward added by _Max Alekseyev_, Feb 04 2024