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 A122980 Number of distributive sublattices of the lattice of k-tuples less than the n-th partition (in Mathematica order), that include the maximum element. 3

%I

%S 2,4,7,8,21,45,16,58,84,200,500,32,152,293,748,1184,3220

%N Number of distributive sublattices of the lattice of k-tuples less than the n-th partition (in Mathematica order), that include the maximum element.

%C After a(18) - for partition [1^5] - the sequence continues ?, 64, 384, 938, 2520, 1238, 5591, ?, ?, ?, ?, ?, 128.

%e For a(5), partition [2,1], the lattice consists of the 6 pairs (i,j) where 0<=i<=2 and 0<=j<=1, with (i,j) <= (i',j') iff i<=i' and j<=j'. {(2,1), (2,0), (0,1), (0,0)} is one distributive sublattice.

%Y Cf. A122977, A122979, A122982, A080577, A074139.

%K nonn,more

%O 1,1

%A _Franklin T. Adams-Watters_, Sep 21 2006

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Last modified May 6 16:29 EDT 2021. Contains 343586 sequences. (Running on oeis4.)