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Denominator of the coefficients in the expansion of 1/W(x) - 1/x where W(x) is the Lambert W function.
2

%I #12 Jan 08 2021 14:48:29

%S 1,2,3,8,15,144,35,5760,2835,44800,6237,43545600,25025,6706022400,

%T 13030875,229605376,10854718875,376610217984000,282907625,

%U 128047474114560000,311834363841,166487326720000,407510816383125,26976017466662584320000,62628675484375

%N Denominator of the coefficients in the expansion of 1/W(x) - 1/x where W(x) is the Lambert W function.

%C If prefixed by an additional 1, denominators of coefficients of expansion of exp(W(x)). - _N. J. A. Sloane_, Jan 08 2021

%e Coefficients of expansion of exp(W(x)) are 1, 1, -1/2, 2/3, -9/8, 32/15, -625/144, 324/35, -117649/5760, 131072/2835, -4782969/44800, ... - _N. J. A. Sloane_, Jan 08 2021

%t CoefficientList[Series[1/ProductLog[x] - 1/x, {x, 0, 21}], x] // Denominator

%Y Numerators are in A264234.

%Y Similar to but strictly different from A230284.

%K nonn,frac

%O 0,2

%A _Peter Luschny_, Nov 09 2015