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A225357
Decimal expansion of (4/7)*(43/57)^(4/3).
1
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, 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, 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
OFFSET
0,1
COMMENTS
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).
LINKS
Steven Weinberg, Goldstone bosons as fractional cosmic neutrinos, arXiv:1305.1971 [astro-ph.CO], 2013.
FORMULA
Equals decimal expansion of 172*(43/57)^(1/3)/399.
EXAMPLE
0.3924220641608327323408794203612644413782408855111339...
MATHEMATICA
RealDigits[(4/7)*(43/57)^(4/3), 10, 110][[1]] (* T. D. Noe, Jun 03 2013 *)
PROG
(Sage) numerical_approx((4/7)*(43/57)^(4/3), digits=115) # G. C. Greubel, Mar 19 2022
CROSSREFS
Sequence in context: A194807 A114875 A275371 * A201664 A103824 A155080
KEYWORD
nonn,cons
AUTHOR
Omar E. Pol, May 28 2013
STATUS
approved