login
A329209
Decimal expansion of the fundamental frequency of the note D4 in hertz.
10
2, 9, 3, 6, 6, 4, 7, 6, 7, 9, 1, 7, 4, 0, 7, 5, 6, 0, 2, 6, 2, 7, 8, 3, 0, 1, 3, 8, 6, 0, 5, 7, 9, 6, 1, 0, 4, 8, 0, 7, 2, 5, 8, 4, 6, 7, 7, 7, 5, 4, 3, 6, 2, 5, 3, 2, 6, 5, 7, 3, 5, 7, 8, 6, 7, 4, 5, 8, 8, 5, 4, 6, 9, 2, 5, 0, 5, 0, 6, 2, 4, 5, 2, 1, 7, 2, 5, 9, 5, 0, 0
OFFSET
3,1
COMMENTS
In 12-tone equal temperament, when A4 (the fifth A on the Piano keyboard) is tuned to 440 Hz, the frequency of the note D4 (7 semitones below A4) is 440*2^(-7/12) Hz = 293.7 Hz.
FORMULA
Equals 220 * 2^(5/12).
EXAMPLE
Frequencies of notes in an octave (Hz):
>--------------------------------------------------
|
| C4 261.6255653005... (A329207)
| +---------------------------------------
>----------| C#4/Db4 277.1826309768... (A329208)
| +---------------------------------------
| D4 293.6647679174... (this seq)
| +---------------------------------------
>----------| D#4/Eb4 311.1269837220... (A329210)
| +---------------------------------------
| E4 329.6275569128... (A329211)
|
>--------------------------------------------------
|
| F4 349.2282314330... (A329212)
| +---------------------------------------
>----------| F#4/Gb4 369.9944227116... (A329213)
| +---------------------------------------
| G4 391.9954359817... (A329214)
| +---------------------------------------
>----------| G#4/Ab4 415.3046975799... (A329215)
| +---------------------------------------
| A4 440.0000000000
| +---------------------------------------
>----------| A#4/Bb4 466.1637615180... (A329217)
| +---------------------------------------
| B4 493.8833012561... (A329218)
|
>--------------------------------------------------
[New layout from Jon E. Schoenfield, Nov 08 2019]
MATHEMATICA
RealDigits[440 1/Surd[2^7, 12], 10, 120][[1]] (* Harvey P. Dale, Aug 01 2021 *)
PROG
(PARI) default(realprecision, 100); 440 * 2^(-7/12)
CROSSREFS
See the Example section above for the fundamental frequency of some other notes.
Sequence in context: A275838 A323720 A021777 * A095802 A334472 A243448
KEYWORD
nonn,easy,cons
AUTHOR
Jianing Song, Nov 08 2019
STATUS
approved