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%I #14 Nov 26 2018 04:06:53
%S 1,-1,0,0,4,34,274,2312,21034,207790,2228892,25890642,324477994,
%T 4370180744,63007469346,968847653702,15834053988732,274170226919434,
%U 5015004366420178,96645631069563928,1957433140982004026
%N a(n) = 2*A052186(n) - n!.
%H Vaclav Kotesovec, <a href="/A201684/b201684.txt">Table of n, a(n) for n = 0..446</a>
%H J.-L. Baril, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v18i1p178">Classical sequences revisited with permutations avoiding dotted pattern</a>, Electronic Journal of Combinatorics, 18 (2011), #P178. See Table 1.
%F a(n) ~ n! * (1 - 4/n + 2/n^2 - 2/n^3 - 18/n^4 - 118/n^5 - 948/n^6 - 9120/n^7 - 100728/n^8 - 1250770/n^9 - 17245316/n^10), for coefficients see 2*A256168. - _Vaclav Kotesovec_, Mar 17 2015
%Y Cf. A052186, A256168.
%K sign
%O 0,5
%A _N. J. A. Sloane_, Dec 03 2011