A114493 Decimal expansion of log_10(4).

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, 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, 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

Offset

0,1

Comments

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

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Catalan Number

Eric Weisstein's World of Mathematics, Central Binomial Coefficient

Wikipedia, Decibel

Index entries for transcendental numbers

Formula

A016627 divided by A002392. Two times A007524. - R. J. Mathar, Feb 21 2013

Example

0.602059991...

Maple

log10(4.0) ; # R. J. Mathar, Feb 21 2013

Mathematica

RealDigits[Log[10, 4], 10, 100][[1]] (* Vincenzo Librandi, Sep 10 2013 *)

Prog

(PARI) log(4)/log(10) \\ Charles R Greathouse IV, Aug 04 2020

Crossrefs

Cf. A000108, A114466.

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).

Sequence in context: A304334 A303535 A269340 * A367309 A081823 A081802

Adjacent sequences: A114490 A114491 A114492 * A114494 A114495 A114496

Keyword

nonn,cons,easy

Author

Eric W. Weisstein, Dec 01 2005

Status

approved