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 A341300 #26 Sep 27 2024 23:00:49 %S A341300 10,34,154,873,5908,46205,408966,4037047,43948808,522910089, %T A341300 6749568010,93924230411,1401558681612,22323869568013,378005070643214, %U A341300 6780291598080015,128424084332544016,2561305169719296017,53651891654000640018,1177646217057902592019 %N A341300 a(n) = n! + (n-1)! + (n-2)! + (n-3)! + n - 3. %C A341300 a(n) is an upper bound for the length of a minimal superpermutation on n symbols (see links). A lower bound is given by A376269(n). - _Paolo Xausa_, Sep 27 2024 %H A341300 Michael De Vlieger, <a href="/A341300/b341300.txt">Table of n, a(n) for n = 3..449</a> %H A341300 Michael Engen and Vincent Vatter, <a href="https://doi.org/10.1080/00029890.2021.1835384">Containing all permutations</a>, Amer. Math. Monthly, 128 (2021), 4-24; <a href="https://arxiv.org/abs/1810.08252">arXiv preprint</a>, arXiv:1810.08252 [math.CO], 2018-2020. %H A341300 Wikipedia, <a href="https://en.wikipedia.org/wiki/Superpermutation">Superpermutation</a>. %F A341300 a(n) = (n-3)!*(n^2*(n-2) + 1) + n - 3. - _Chai Wah Wu_, Sep 20 2024 %t A341300 Array[Total[(# - Range[0, 3])!] + # - 3 &, 20, 3] (* _Michael De Vlieger_, Apr 07 2021 *) %o A341300 (Python) %o A341300 from sympy import factorial %o A341300 def A341300(n): return (n**2*(n-2)+1)*factorial(n-3)+n-3 # _Chai Wah Wu_, Sep 20 2024 %Y A341300 Cf. A180632, A332089, A376269. %K A341300 nonn %O A341300 3,1 %A A341300 _N. J. A. Sloane_, Feb 13 2021