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%I #11 Nov 04 2017 18:33:27
%S 2,2,10,3430,281192563951390,
%T 1766847064778382532572997586311708103976882383055495099549785723721857950
%N 4^n! - 3^n! + 2^n! - 1.
%C The next term has 434 digits. - _Harvey P. Dale_, Nov 04 2017
%F a(n)=4^n!-3^n!+2^n!-1.
%e For n=2, a(2)=4^2!-3^2!+2^2!-1=16-9+4-1=10.
%t 4^#-3^#+2^#-1&/@(Range[0,5]!) (* _Harvey P. Dale_, Nov 04 2017 *)
%o (PARI) a(n)=(k->4^k-3^k+2^k-1)(n!) \\ _Charles R Greathouse IV_, Jan 23 2014
%Y Cf. A203925, A236368.
%K nonn
%O 0,1
%A _Assoul Abdelkarim_, Jan 23 2014
%E a(4)-a(5) from _Charles R Greathouse IV_, Jan 23 2014
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