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A176337 a(n) = 1 + (1-2^n)*a(n-1) for n > 0, a(0)=0.

%I A176337 #18 Sep 08 2022 08:45:52
%S A176337 0,1,-2,15,-224,6945,-437534,55566819,-14169538844,7240634349285,
%T A176337 -7407168939318554,15162474818785080039,-62090334382924902759704,
%U A176337 508581928930537878504735465,-8332097741669002063543081123094
%N A176337 a(n) = 1 + (1-2^n)*a(n-1) for n > 0, a(0)=0.
%H A176337 G. C. Greubel, <a href="/A176337/b176337.txt">Table of n, a(n) for n = 0..80</a>
%p A176337 A176337 := proc(n)
%p A176337     if n = 0 then
%p A176337         0;
%p A176337     else
%p A176337         1+(1-2^n)*procname(n-1) ;
%p A176337     end if;
%p A176337 end proc: # _R. J. Mathar_, May 04 2013
%t A176337 a[n_, q_]:= a[n, q]= If[n==0, 0, (1-q^n)*a[n-1, q] +1]; Table[a[n, 2], {n,0,15}]
%o A176337 (PARI) q=2; a(n,q) = if(n==0, 0, 1 -(q^n-1)*a(n-1,q) );
%o A176337 vector(15, n, a(n-1, 2)) \\ _G. C. Greubel_, Dec 07 2019
%o A176337 (Magma)
%o A176337 function a(n,q)
%o A176337   if n eq 0 then return 0;
%o A176337   else return 1 - (q^n-1)*a(n-1,q);
%o A176337   end if; return a; end function;
%o A176337 [a(n,2): n in [0..15]]; // _G. C. Greubel_, Dec 07 2019
%o A176337 (Sage)
%o A176337 def a(n, q):
%o A176337     if (n==0): return 0
%o A176337     else: return 1 - (q^n-1)*a(n-1,q)
%o A176337 [a(n,2) for n in (0..15)] # _G. C. Greubel_, Dec 07 2019
%o A176337 (GAP)
%o A176337 a:= function(n,q)
%o A176337     if n=0 then return 0;
%o A176337     else return 1 - (q^n-1)*a(n-1,q);
%o A176337     fi; end;
%o A176337 List([0..15], n-> a(n,2) ); # _G. C. Greubel_, Dec 07 2019
%Y A176337 Cf. A176338.
%K A176337 sign,easy
%O A176337 0,3
%A A176337 _Roger L. Bagula_, Apr 15 2010