释义 |
Comma of PythagorasThe musical interval by which twelve fifths exceed seven octaves,
Successive Continued Fraction Convergents to give increasingly closeapproximations of fifths by octaves as 1, 2, 5/3, 12/7, 41/24, 53/31, 306/179, 665/389, ...(Sloane's A005664and A046102; Jeans 1968, p. 188), shown in bold in the table below. All near-equalities of fifths and octaves having
with are given in the following table.
 |  | Ratio |  |  | Ratio | 12 | 7 | 1.013643265 | 265 | 155 | 1.010495356 | 41 | 24 | 0.9886025477 | 294 | 172 | 0.9855324037 | 53 | 31 | 1.002090314 | 306 | 179 | 0.9989782832 | 65 | 38 | 1.015762098 | 318 | 186 | 1.012607608 | 94 | 55 | 0.9906690375 | 347 | 203 | 0.9875924759 | 106 | 62 | 1.004184997 | 359 | 210 | 1.001066462 | 118 | 69 | 1.017885359 | 371 | 217 | 1.014724276 | 147 | 86 | 0.9927398469 | 400 | 234 | 0.9896568543 | 159 | 93 | 1.006284059 | 412 | 241 | 1.003159005 | 188 | 110 | 0.9814251419 | 424 | 248 | 1.016845369 | 200 | 117 | 0.994814985 | 453 | 265 | 0.9917255479 | 212 | 124 | 1.008387509 | 465 | 272 | 1.005255922 | 241 | 141 | 0.9834766286 | 477 | 279 | 1.018970895 | 253 | 148 | 0.9968944607 | 494 | 289 | 0.9804224033 |
See also Comma of Didymus, Diesis, Schisma References
Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, p. 257, 1995.Guy, R. K. ``Small Differences Between Powers of 2 and 3.'' §F23 in Unsolved Problems in Number Theory, 2nd ed. New York: Springer-Verlag, p. 261, 1994. Sloane, N. J. A. Sequences A005664/M1428 and A046102 in ``An On-Line Version of the Encyclopedia of Integer Sequences.''http://www.research.att.com/~njas/sequences/eisonline.html.
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