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A329215
Decimal expansion of the fundamental frequency of the note G#4/Ab4 in hertz.
10
4, 1, 5, 3, 0, 4, 6, 9, 7, 5, 7, 9, 9, 4, 5, 1, 3, 8, 5, 2, 2, 4, 4, 1, 7, 8, 8, 9, 3, 3, 7, 1, 5, 1, 2, 5, 4, 4, 3, 3, 3, 0, 0, 5, 3, 4, 6, 9, 0, 4, 6, 8, 3, 8, 0, 4, 6, 5, 3, 5, 0, 6, 2, 6, 2, 0, 0, 4, 6, 0, 5, 4, 6, 0, 5, 0, 3, 0, 9, 4, 9, 3, 3, 9, 8, 8, 7, 3, 2, 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 G#4/Ab4 (1 semitone below A4) is 440*2^(-1/12) Hz = 415.3 Hz.
FORMULA
Equals 220 * 2^(11/12).
EXAMPLE
Frequencies of notes in an octave (Hz):
>--------------------------------------------------
|
| C4 261.6255653005... (A329207)
| +---------------------------------------
>----------| C#4/Db4 277.1826309768... (A329208)
| +---------------------------------------
| D4 293.6647679174... (A329209)
| +---------------------------------------
>----------| 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... (this seq)
| +---------------------------------------
| A4 440.0000000000
| +---------------------------------------
>----------| A#4/Bb4 466.1637615180... (A329217)
| +---------------------------------------
| B4 493.8833012561... (A329218)
|
>--------------------------------------------------
[New layout from Jon E. Schoenfield, Nov 08 2019]
MATHEMATICA
First[RealDigits[220*2^(11/12), 10, 100]] (* Paolo Xausa, Jun 18 2024 *)
PROG
(PARI) default(realprecision, 100); 440 * 2^(-1/12)
CROSSREFS
See the Example section above for the fundamental frequency of some other notes.
Sequence in context: A067061 A115210 A199150 * A214892 A030352 A212643
KEYWORD
nonn,easy,cons
AUTHOR
Jianing Song, Nov 08 2019
STATUS
approved