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A349947 Triangular array: row n gives the positions of n+1 in A349946.

%I A349947 #12 Jun 05 2023 08:55:38
%S A349947 1,2,4,3,5,9,6,7,10,16,8,11,12,17,25,13,14,18,19,26,36,15,20,21,27,28,
%T A349947 37,49,22,23,29,30,38,39,50,64,24,31,32,40,41,51,52,65,81,33,34,42,43,
%U A349947 53,54,66,67,82,100,35,44,45,55,56,68,69,83,84,101,121
%N A349947 Triangular array: row n gives the positions of n+1 in A349946.
%C A349947 Every positive integer occurs exactly once, so as a sequence, this is a permutation of the positive integers.
%C A349947 Row n ends in n^2. The first term in row n is (1 + n/1)^2 - 3 if n >= 4 and n is even; as in A028872(n) for n >= 3.
%C A349947 The first term in row n is ((n+1)/2)^2 - 1 if n >= 3 and n is odd, as in A132411(n) for n >= 3.
%e A349947 First 7 rows:
%e A349947    1
%e A349947    2   4
%e A349947    3   5   9
%e A349947    6   7  10  16
%e A349947    8  11  12  17  25
%e A349947   13  14  18  19  26  36
%e A349947   14  20  21  27  28  37  49
%t A349947 t = {1, 1}; Do[t = Join[t, Riffle[Range[n], n], {n}], {n, 2, 100}];
%t A349947 u = Flatten[Partition[t, 2]];
%t A349947 v = Table[n (n + 1), {n, 1, 80}];
%t A349947 d = Delete[u, Map[{#} &, v]]; (* A349526 *)
%t A349947 p = Table[{d[[n]], d[[n + 1]]}, {n, 1, 150}];
%t A349947 q = Map[Total, p]  (* A349946 *)
%t A349947 r = Table[Flatten[Position[q, n]], {n, 2, 12}]  (* A349947 array *)
%t A349947 Flatten[r]  (* A349947 sequence *)
%Y A349947 Cf. A349526, A349946.
%K A349947 nonn,tabl
%O A349947 1,2
%A A349947 _Clark Kimberling_, Dec 07 2021