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A117537
Locations of the midpoints of consecutive zeros of the Riemann zeta function on the critical line with increasingly large normalized spacing.
3
2, 3, 5, 7, 12, 19, 31, 46, 53, 72, 270, 311, 954, 1178, 1308, 1395, 1578, 3395, 4190
OFFSET
0,1
COMMENTS
Equivalently, locations of consecutive real zeros of the Z function. If t and s are consecutive zeros of the Z function, we define their normalized spacing as (s-t)*log((s+t)/(4*Pi)). The sequence above is found by taking r = log(2)(s+t)/(4*Pi) and rounding to the nearest integer. These values r have a marked tendency to be close to integer values and all of the terms of the above sequence are actually contained in the intervals [s, t]*log(2)/(2*Pi).
So far as the first 100000 zeros take us, the integers of the above sequence actually fall inside the normalized intervals of zeros of Z; that is, they fall between two zeros of Z(2*Pi*t/log(2)). It would be a worthwhile project to push this computation far enough to find a counterexample. The integers above, while slightly less clearly linked to music than A117536 and A117538, are nevertheless very clearly closely related to equal divisions of the octave. Large gaps between consecutive zeros, in other words, seem to correspond to good scale divisions, though less exactly than peak values or high integrals do.
REFERENCES
Edwards, H. M., Riemann's Zeta-Function, Academic Press, 1974
A. Ivic (1985). The Riemann Zeta Function, John Wiley & Sons. ISBN 0-471-80634-X.
Titchmarsh, E. C., The Theory of the Riemann Zeta-Function, second revised (Heath-Brown) edition, Oxford University Press, 1986
CROSSREFS
KEYWORD
hard,nonn
AUTHOR
Gene Ward Smith, Mar 27 2006
STATUS
approved