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Number of ordered set partitions of [n] where k = two is minimal such that for each block b the smallest integer interval containing b has at most k elements.
2

%I #5 Oct 17 2018 16:42:09

%S 1,4,20,114,750,5616,47304,443400,4582200,51790320,635791680,

%T 8426915280,119960552880,1825701857280,29585590473600,508653914267520,

%U 9248148480574080,177303557272262400,3574966680853747200,75628468328518828800,1675003757666567328000

%N Number of ordered set partitions of [n] where k = two is minimal such that for each block b the smallest integer interval containing b has at most k elements.

%H Alois P. Heinz, <a href="/A320615/b320615.txt">Table of n, a(n) for n = 2..450</a>

%Y Column k=2 of A276891.

%K nonn

%O 2,2

%A _Alois P. Heinz_, Oct 17 2018