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%I #15 May 24 2012 13:06:49
%S 1,3,6,6,11,11,18,18,18,18,29,29,29,29,44,44,44,44,44,44,44,66,66,66,
%T 66,66,66,66,66,96,96,96,96,96,96,96,96,96,96,96,96,138,138,138,138,
%U 138,138,138,138,138,138,138,138,138,138,194,194,194,194,194,194,194,194,194,194,194,194,194,194,194
%N Number of parts that are visible in one of the three views of the shell model of partitions with n regions mentioned in A210991.
%C For the definition of "regions of n" see A206437.
%F a(A000041(n)) = A026905(n).
%e Written as a triangle begins:
%e 1,
%e 3,
%e 6,
%e 6, 11,
%e 11,18,
%e 18,18,18,29,
%e 29,29,29,44,
%e 44,44,44,44,44,44,66,
%e 66,66,66,66,66,66,66,96,
%e 96,96,96,96,96,96,96,96,96,96,96,138;
%Y Row j has length A187219(j). Right border gives A026905.
%Y Cf. A000041, A135010, A138121, A182703, A186114, A194803, A194805, A206437, A210991.
%K nonn,tabf
%O 1,2
%A _Omar E. Pol_, May 24 2012