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%I #32 Dec 22 2021 07:40:10
%S 17,17,19,19,19,19,19,23,23,31,31,31,7,7,7,7,7,37,37,41,43,43,43,43,
%T 43,43,2,43,2,43,2,47,47,47,47,47,47,2,47,2,47,2,47,2,53,61,61,61,61,
%U 61,61,5,5,5,67,71,11,11,73,73,73,73,73,73,73,73,73,73,73
%N For g=A201557(n), define a(n) as the prime p|g such that G(g/p) is maximum, where G(k) = sigma(k)/(k*log(log(k))).
%C The ratio G(A201557(n)/p)/G(A201557(n)) is defined by Nicolas as the Gronwall quotient (A201557 = proper GA1 numbers).
%H Michel Marcus, <a href="/A216436/b216436.txt">Table of n, a(n) for n = 1..1000</a>
%H G. Caveney, J.-L. Nicolas and J. Sondow, <a href="http://arxiv.org/abs/1112.6010">On SA, CA, and GA numbers</a>, Ramanujan J., 29 (2012), 359-384.
%H J.-L. Nicolas, <a href="http://math.univ-lyon1.fr/~nicolas/GA160">Table of proper GA1 numbers up to 10^60</a>, 2011.
%H J.-L. Nicolas, <a href="http://math.univ-lyon1.fr/~nicolas/GAnumbers.html">Computation of GA1 numbers</a>, 2011.
%F G(A201557(n)/a(n)) >= G(A201557(n)/q) if prime q|A201557(n).
%p # See link "Computation of GA1 numbers".
%o (PARI) findq(i) = {f = factor(i); maxqu = 0.0; qmax = 0; for(iq=1, length(f~), qq = f[iq,1]; qu = g(i/qq)/g(i); if (qu > maxqu, maxqu = qu; qmax = qq;) ); return (qmax);} \\ for i in A201557
%Y Cf. A000203, A201557, A197638.
%K nonn
%O 1,1
%A _Michel Marcus_, Sep 10 2012
%E Definition simplified and formula supplied by _Jonathan Sondow_, Sep 11 2012
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