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%I #18 Dec 21 2020 23:02:49
%S 1,2,6,60,840,360360,232792560,5342931457063200,
%T 591133442051411133755680800,
%U 79057815923102180093748328364591874435251553600
%N a(n) is the common denominator of the A338197(n) rational resistance values that can be obtained from a network of exactly n one-ohm resistors, but not by a network of fewer than n one-ohm resistors.
%C The next terms a(11)=8.87124454467...*10^84 and a(12)=1.80685581583...*10^141 are too big to be included in the data.
%H Hugo Pfoertner, <a href="/A338600/b338600.txt">Table of n, a(n) for n = 1..15</a>
%e a(4) = 60: The resistance values for which a minimum of 4 resistors is needed are [1/4, 2/5, 3/5, 3/4, 4/3, 5/3, 5/2, 4] with a common denominator of 60.
%e a(1) = 1: [1],
%e a(2) = 2: [1/2, 2],
%e a(3) = 6: [1/3, 2/3, 3/2, 3].
%Y Cf. A048211, A051389, A180414, A337517, A338197, A338580, A338590, A338595, A338596, A338597, A338598, A338599, A338605, A338606, A338607, A338608, A338609.
%K nonn
%O 1,2
%A _Hugo Pfoertner_, Nov 03 2020