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A239483 Number of (3,0)-separable partitions of n; see Comments.

%I A239483 #11 Jan 28 2022 01:06:34
%S A239483 0,1,1,1,1,3,3,4,5,7,8,10,12,16,18,22,26,33,38,45,53,65,75,89,103,124,
%T A239483 143,168,195,230,265,309,357,418,479,556,639,742,850,979,1122,1294,
%U A239483 1478,1696,1935,2220,2528,2889,3287,3752,4261,4850,5502,6257,7084
%N A239483 Number of (3,0)-separable partitions of n; see Comments.
%C A239483 Suppose that p is a partition of n into 2 or more parts and that h is a part of p. Then p is (h,0)-separable if there is an ordering x, h, x, h, ..., h, x of the parts of p, where each x represents any part of p except h. Here, the number of h's on the ends of the ordering is 0. Similarly, p is (h,1)-separable if there is an ordering x, h, x, h, ..., x, h, where the number of h's on the ends is 1; next, p is (h,2)-separable if there is an ordering h, x, h, ..., x, h. Finally, p is h-separable if it is (h,i)-separable for i = 0,1,2.
%e A239483 The (3,0)-separable partitions of 11 are 731, 632, 434, 23231, so that a(11) = 4.
%t A239483 z = 65; -1 + Table[Count[IntegerPartitions[n], p_ /; 2 Count[p, 1] == Length[p] - 1], {n, 2, z}]  (* A165652 *)
%t A239483 -1 + Table[Count[IntegerPartitions[n], p_ /; 2 Count[p, 2] == Length[p] - 1], {n, 3, z}]  (* A239482 *)
%t A239483 -1 + Table[Count[IntegerPartitions[n], p_ /; 2 Count[p, 3] == Length[p] - 1], {n, 4, z}]  (* A239483 *)
%t A239483 -1 + Table[Count[IntegerPartitions[n], p_ /; 2 Count[p, 4] == Length[p] - 1], {n, 5, z}]  (* A239484 *)
%t A239483 -1 + Table[Count[IntegerPartitions[n], p_ /; 2 Count[p, 5] == Length[p] - 1], {n, 6, z}] (* A239485 *)
%Y A239483 Cf. A239467, A165652, A239482, A239484, A239485.
%K A239483 nonn,easy
%O A239483 4,6
%A A239483 _Clark Kimberling_, Mar 20 2014