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%I #4 May 26 2024 02:33:45
%S 1,-1,3,1,-1,3,1,-1,3,1,-2,4,1,-2,4,1,-1,3,1,-1,3,1,-3,5,1,-3,5,1,-1,
%T 3,1,-1,3,1,-2,4,1,-2,4,1,-1,3,1,-1,3,1,-4,6,1,-4,6,1,-1,3,1,-1,3,1,
%U -2,4,1,-2,4,1,-1,3,1,-1,3,1,-3,5,1,-3,5,1,-1,3,1,-1,3,1,-2,4,1,-2,4
%N First differences of A101684.
%C Presumably the sequence can be derived from A007814.
%F a(n) = A101684(n+1) - A101684(n). - _Wesley Ivan Hurt_, May 26 2024
%t Differences[IntegerExponent[Denominator[With[{nn = 80}, CoefficientList[Series[Exp[-1 + Sqrt[1 + x]], {x, 0, nn}], x] Range[0, nn]!]], 2]] (* _Wesley Ivan Hurt_, May 26 2024 after _Harvey P. Dale_ *)
%Y Cf. A007814, A101684.
%K sign
%O 0,3
%A _Ralf Stephan_, Dec 13 2004