A284433 - OEIS

%I #10 Feb 06 2025 21:33:33

%S 1,2,6,2,18,12,24,24,1320,240,528,720,5664,105888,16992,150048,244800,

%T 4266432,4375296,39598848,50637312,123310080,202549248,15925690368,

%U 3765657600,23454351360,101739110400,437749678080,1572538613760,11891771080704,7862693068800,185042766200832

%N The number of positive integer sequences of length n with no duplicate substrings (forward or backward) of length greater than 1, every number different from its neighbors, and a minimal sum (= A282167(n)).

%e For n = 4 the a(4) = 2 solutions are [1,3,2,1] and [1,2,3,1].

%Y Cf. A282167, A283558, A284431, A284432, A284436.

%K nonn

%O 1,2

%A _Peter Kagey_, Mar 27 2017

%E Terms a(10) onward from _Max Alekseyev_, Feb 06 2025