%I #7 Sep 08 2022 08:45:50
%S 5,5,11,35,143,719,4319,30239,241919,2177279,21772799,239500799,
%T 2874009599,37362124799,523069747199,7846046207999,125536739327999,
%U 2134124568575999,38414242234367999,729870602452991999
%N 6*n! - 1.
%H Vincenzo Librandi, <a href="/A173316/b173316.txt">Table of n, a(n) for n = 0..200</a>
%F a(0)=5, a(n) = n*a(n-1)+n-1. - _Vincenzo Librandi_, Sep 30 2013
%t Table[6 n! - 1, {n, 0, 25}] (* _Vincenzo Librandi_, Sep 30 2013 *)
%o (Magma) [6*Factorial(n)-1: n in [0..25]]; /* or */ [5] cat [n eq 1 select n+4 else n*Self(n-1)+n-1: n in [1..25] ]; // _Vincenzo Librandi_, Sep 30 2013
%Y Cf. sequences of the type k*n!-1: A033312 (k=1), A020543 (k=2), A173323 (k=3), A173321 (k=4), A173317 (k=5).
%K nonn,easy
%O 0,1
%A _Vincenzo Librandi_, Feb 16 2010