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Number of length n inversion sequences avoiding the patterns 101 and 120.
1

%I #5 Jul 17 2024 08:55:44

%S 1,1,2,6,22,90,397,1859,9145,46882,248899,1361845,7650233,43990073,

%T 258287170,1545382674,9406108839,58155261970,364774287298,

%U 2318661708634,14921368078303,97132997631387,639118975577638,4247742637567555,28499086448886207

%N Number of length n inversion sequences avoiding the patterns 101 and 120.

%H Benjamin Testart, <a href="/A374551/b374551.txt">Table of n, a(n) for n = 0..250</a>

%H Benjamin Testart, <a href="https://arxiv.org/abs/2407.07701">Completing the enumeration of inversion sequences avoiding one or two patterns of length 3</a>, arXiv:2407.07701 [math.CO], 2024.

%Y Cf. A113227, A263778, A374545, A374547, A374548.

%K nonn

%O 0,3

%A _Benjamin Testart_, Jul 17 2024