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a(n) = (1/1 - 1/(n-1) + ... + d/binomial(n-[ n/2 ],[ n/2 ]))*L, where L = LCM{1, n-1, ..., binomial(n-[ n/2 ],[ n/2 ])}, d = (-1)^n.
0

%I #4 Mar 30 2012 18:56:04

%S 1,0,1,5,13,-1,41,383,901,-47,1945,26141,29368,-6359,296509,345525,

%T 756291,-197211,10483329,225371001,242537898,-3394965,204481239,

%U 5215763433

%N a(n) = (1/1 - 1/(n-1) + ... + d/binomial(n-[ n/2 ],[ n/2 ]))*L, where L = LCM{1, n-1, ..., binomial(n-[ n/2 ],[ n/2 ])}, d = (-1)^n.

%K sign

%O 0,4

%A _Clark Kimberling_