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A114493 Decimal expansion of log_10(4).

%I A114493 #27 Jul 31 2025 12:59:23
%S A114493 6,0,2,0,5,9,9,9,1,3,2,7,9,6,2,3,9,0,4,2,7,4,7,7,7,8,9,4,4,8,9,8,6,0,
%T A114493 5,3,5,3,6,3,7,9,7,6,2,9,2,4,2,1,7,0,8,2,6,2,0,8,5,4,9,2,2,2,5,4,2,1,
%U A114493 6,3,7,8,5,4,8,8,4,9,0,1,8,9,7,3,8,5,4,5,0,4,2,3,6,3,7,2,3,4,4,0,8,1
%N A114493 Decimal expansion of log_10(4).
%C A114493 In engineering (all branches, but particularly electronic and electrical) power and amplitude ratios are measured rigorously in decibels (dB). This constant, with offset 1 (i.e., 6.02... = 10*A114493) is the dB equivalent of a 2:1 amplitude ratio or, equivalently, 4:1 power ratio. - _Stanislav Sykora_, Dec 11 2013
%H A114493 Vincenzo Librandi, <a href="/A114493/b114493.txt">Table of n, a(n) for n = 0..1000</a>
%H A114493 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CatalanNumber.html">Catalan Number</a>
%H A114493 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CentralBinomialCoefficient.html">Central Binomial Coefficient</a>
%H A114493 Wikipedia, <a href="http://en.wikipedia.org/wiki/Decibel">Decibel</a>
%H A114493 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%F A114493 A016627 divided by A002392. Two times A007524. - _R. J. Mathar_, Feb 21 2013
%F A114493 Equals 1/A154155. - _R. J. Mathar_, Jul 31 2025
%e A114493 0.602059991...
%p A114493 log10(4.0) ; # _R. J. Mathar_, Feb 21 2013
%t A114493 RealDigits[Log[10, 4], 10, 100][[1]] (* _Vincenzo Librandi_, Sep 10 2013 *)
%o A114493 (PARI) log(4)/log(10) \\ _Charles R Greathouse IV_, Aug 04 2020
%Y A114493 Cf. A000108, A114466.
%Y A114493 Cf. decimal expansion of log_10(m): A007524 (m=2), A114490 (m=3), this sequence, A153268 (m=5), A153496 (m=6), A153620 (m=7), A153790 (m=8), A104139 (m=9),  A154182 (m=11), A154203 (m=12), A154368 (m=13), A154478 (m=14), A154580 (m=15), A154794 (m=16), A154860 (m=17), A154953 (m=18), A155062 (m=19), A155522 (m=20), A155677 (m=21), A155746 (m=22), A155830 (m=23), A155979 (m=24).
%K A114493 nonn,cons,easy
%O A114493 0,1
%A A114493 _Eric W. Weisstein_, Dec 01 2005