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RePoSS #11: The Mathematics of Niels Henrik Abel: Continuation ...

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370 Chapter 19. <strong>The</strong> Paris memoir<br />

which allowed him to rewrite (19.31) as<br />

α =<br />

=<br />

n−1<br />

∑ hqk + n − 1 − (hr − µ) + A<br />

k=1<br />

n−1<br />

∑ hqk −<br />

k=1<br />

n<br />

∑ hθ (yk) + n − 1 + A + µ. (19.32)<br />

k=1<br />

<strong>The</strong>refore, ABEL turned to algebraically manipulating the “degrees” hθ (y k) along the<br />

same lines as had been followed in describing γ above.<br />

Obviously, from the inequality<br />

and the formula<br />

ABEL obtained<br />

hθ (y) ≥ h (qmy m ) for each m = 0, . . . , n − 1,<br />

h (qmy m ) = hqm + mhy,<br />

hθ (y k) ≥ hqm + mhy k for k = 1, . . . , n.<br />

Designating by ρτ the index <strong>of</strong> the maximal value <strong>of</strong> h (qmy m ) within the τ’th sequence<br />

<strong>of</strong> roots, ABEL employed the same machinery which had served him before, although<br />

this time in a slightly different notational dressing. Summing the excesses ε τ,k within<br />

the τ’th sequence,<br />

nτµτ−1<br />

∑ ετ,k = Cτ,<br />

k=1<br />

ABEL found by the manipulations and number theoretic results<br />

or less specifically (Cτ ≥ 0)<br />

µ − α ≥ γ − A +<br />

µ − α ≥ γ − A.<br />

ε<br />

∑ Cτ,<br />

τ=1<br />

However, the inequality in (19.33) was actually an equality,<br />

µ − α = γ − A, (19.33)<br />

as ABEL deduced by another tedious sequence <strong>of</strong> manipulations.<br />

Specializing the relation expressed (19.33) to the other case (in which F0 (x) = 1)<br />

led to the result that if r did not contain any factors independent <strong>of</strong> the indeterminate<br />

quantities, then<br />

µ − α = γ.<br />

ABEL concluded these investigations by considering situations in which the coef-<br />

ficients q0, . . . , qn−1 were subjected to some kinds <strong>of</strong> conditions. Again arguing very<br />

“generally”, ABEL could claim that the result (19.33) would not generally be substan-<br />

tially altered, although the constant A should reflect the additional conditions.<br />

In the paper’s eighth section, ABEL applied the results obtained thus far to calcu-<br />

late γ in an example for which n = 13.

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