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%I #7 Sep 04 2016 17:20:31
%S 1,1,1,-1,1,1,1,-1,1,-1,1,-1,1,-1,1,-1,1,1,1,-1,1,-1,-1,2,1,-1,-1,2,1,
%T -1,1,-1,-1,2,1,-1,-1,-1,1,-1,2,1,-1,-1,2,1,-1,-1,-1,-1,1,-1,1,-1,1,
%U -1,1,1,1,-1,1,-1,-1,2,1,-1,-1,-1,1,-1,1,1,1,-1,-1,-1,1,-1,2,1,-1,1,-1,-1,-1,1,1,1,-1,1,1,1,-1
%N a(n) = (A274647(n)-A274647(n-1)) / n.
%C a(n) tells what k was finally used when determining the value of A274647(n), with minus sign if subtraction was chosen and with positive sign if addition was chosen.
%C First 1 occurs at n=1, first 2 at n=24, first 3 at n=128, first 4 at n=204, first 5 at n=17903, first 6 at n=210027.
%C First -1 occurs at n=4, first -2 at n=124, first -3 at n=5882.
%H Antti Karttunen, <a href="/A276438/b276438.txt">Table of n, a(n) for n = 1..17903</a>
%F a(n) = (A274647(n)-A274647(n-1)) / n.
%o (Scheme) (define (A276438 n) (/ (- (A274647 n) (A274647 (- n 1))) n))
%Y Cf. A274647.
%Y Cf. A276439 (partial sums).
%K sign
%O 1,24
%A _Antti Karttunen_, Sep 04 2016