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a(n) is the denominator of x(n) = (16*x(n-1) + (120*n^2 - 89*n + 16)/(512*n^4 - 1024*n^3 + 712*n^2 - 206*n + 21)) mod 1, with x(0) = 0.
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%I #21 Jul 14 2024 15:15:37

%S 1,15,4095,765765,111035925,78058255275,24536311574775,

%T 81926744348173725,154923473562396513975,154923473562396513975,

%U 595232293160786606325,76784965817741472215925,321191512015612578279214275,3146713243216956429401462252175,342991743510648250804759385487075

%N a(n) is the denominator of x(n) = (16*x(n-1) + (120*n^2 - 89*n + 16)/(512*n^4 - 1024*n^3 + 712*n^2 - 206*n + 21)) mod 1, with x(0) = 0.

%C See A374334 for details and links.

%H Paolo Xausa, <a href="/A374335/b374335.txt">Table of n, a(n) for n = 0..375</a>

%t Block[{n = 0}, Denominator[NestList[Mod[16*# + (120*(++n)^2 - 89*n + 16)/(512*n^4 - 1024*n^3 + 712*n^2 - 206*n + 21), 1] &, 0, 20]]]

%Y Cf. A374333, A374334 (numerators), A374581, A374608.

%K nonn,frac

%O 0,2

%A _Paolo Xausa_, Jul 06 2024