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%I #11 Feb 15 2016 09:30:35
%S 1,16,175,1771,17906,184920,1958979,21253375,235401166,2653427140,
%T 30356604642,351714783980,4119532070980,48708027030608,
%U 580682498991627,6973355148949335,84286653134676230,1024694093358751200,12522664845237058050,153762682169941498170
%N Number of sequences in {1,...,n}^n with longest increasing subsequence of length two.
%H Alois P. Heinz, <a href="/A268869/b268869.txt">Table of n, a(n) for n = 2..900</a>
%F a(n) = A239295(n) - A088218(n) = A239295(n) - A001700(n-1).
%e a(2) = 1: 12.
%e a(3) = 16: 112, 113, 121, 122, 131, 132, 133, 212, 213, 223, 231, 232, 233, 312, 313, 323.
%e a(4) = 175: 1112, 1113, 1114, 1121, ..., 4414, 4423, 4424, 4434.
%Y Column k=2 of A245667.
%Y Cf. A001700, A088218, A239295.
%K nonn,easy
%O 2,2
%A _Alois P. Heinz_, Feb 15 2016
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