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

%I #6 Sep 22 2016 07:30:37

%S 1,1,4,29,336,5375,111138,2845864,87597223,3170429794,132647186513,

%T 6328769607152,340517379645028,20469645334387763,1363935094328964210,

%U 100052662656438620359,8032243625863280744704

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

%F a(n) = A276727(2n,n).

%e a(1) = 1: 1|2.

%e a(2) = 4: 12|34, 12|3|4, 1|23|4, 1|2|34.

%e a(3) = 29: 123|456, 123|45|6, 123|46|5, 123|4|56, 123|4|5|6, 12|345|6, 12|35|46, 12|35|4|6, 12|3|456, 12|3|46|5, 13|24|56, 13|24|5|6, 13|2|456, 13|2|45|6, 13|2|46|5, 13|2|4|56, 13|2|4|5|6, 1|234|56, 1|234|5|6, 1|23|456, 1|23|46|5, 1|24|35|6, 1|24|3|56, 1|24|3|5|6, 1|2|345|6, 1|2|35|46, 1|2|35|4|6, 1|2|3|456, 1|2|3|46|5.

%Y Cf. A276727, A276892.

%K nonn

%O 0,3

%A _Alois P. Heinz_, Sep 16 2016