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A382099 a(n) is the denominator of the square of the n-th Lagrange number.

%I A382099 #6 Mar 19 2025 10:03:14
%S A382099 1,1,25,169,841,289,7921,28561,9409,54289,187489,93025,970225,1755625,
%T A382099 2550409,8392609,17480761,32959081,10452289,57168721,82391929,
%U A382099 29953729,216119401,821223649,1119638521,354681889,1871514121,2666792881,967521025,5628750625,9323254249
%N A382099 a(n) is the denominator of the square of the n-th Lagrange number.
%D A382099 John H. Conway and Richard K. Guy, The Book of Numbers, New York: Springer-Verlag, 1996. See p. 187.
%F A382099 a(n) = denominator(9 - 4/A002559(n)^2).
%F A382099 Limit_{n->oo} A382098(n)/a(n) = 9.
%e A382099 5/1 = A002163^2;
%e A382099 8/1 = A010466^2;
%e A382099 221/25 = A200991^2;
%e A382099 1517/169 = A305308^2;
%e A382099 ...
%Y A382099 Cf. A002559, A382098 (numerators).
%Y A382099 Cf. A002163, A010466, A200991, A305308.
%K A382099 nonn,frac
%O A382099 1,3
%A A382099 _Stefano Spezia_, Mar 15 2025