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%I #18 Mar 19 2022 02:33:57
%S 3,9,2,4,2,2,0,6,4,1,6,0,8,3,2,7,3,2,3,4,0,8,7,9,4,2,0,3,6,1,2,6,4,4,
%T 4,1,3,7,8,2,4,0,8,8,5,5,1,1,1,3,3,9,2,5,6,2,8,4,8,8,6,5,4,9,9,5,4,8,
%U 1,9,9,0,2,7,3,3,1,4,8,7,2,7,0,0,1,6,0,8,5,8,7,3,5,2,9,8,5,0,1,0,6,9,3,6,2
%N Decimal expansion of (4/7)*(43/57)^(4/3).
%C Steven Weinberg suggested that the contribution from Goldstone bosons to the effective number of neutrino species present in the era before recombination would be (4/7)*(43/57)^(4/3).
%H Steven Weinberg, <a href="http://arxiv.org/abs/1305.1971">Goldstone bosons as fractional cosmic neutrinos</a>, arXiv:1305.1971 [astro-ph.CO], 2013.
%F Equals decimal expansion of 172*(43/57)^(1/3)/399.
%e 0.3924220641608327323408794203612644413782408855111339...
%t RealDigits[(4/7)*(43/57)^(4/3), 10, 110][[1]] (* _T. D. Noe_, Jun 03 2013 *)
%o (Sage) numerical_approx((4/7)*(43/57)^(4/3), digits=115) # _G. C. Greubel_, Mar 19 2022
%Y Cf. A111728, A225359.
%K nonn,cons
%O 0,1
%A _Omar E. Pol_, May 28 2013