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A374791 Irregular triangle T(n, k), n >= 0, k = 1..A120880(n), read by rows; the n-th lists the integers m such that A374560(m) = n.

%I A374791 #22 May 20 2025 08:55:52
%S A374791 0,1,2,4,3,5,6,7,8,9,11,13,12,17,18,24,10,14,15,16,19,20,22,26,21,23,
%T A374791 25,27,28,29,30,31,32,33,34,35,37,39,41,43,38,42,47,48,51,52,58,62,40,
%U A374791 49,50,60,59,61,70,71,72,73,83,85,84,97,98,112,36,44,45,46,53,54
%N A374791 Irregular triangle T(n, k), n >= 0, k = 1..A120880(n), read by rows; the n-th lists the integers m such that A374560(m) = n.
%C A374791 A374560 corresponds to a square array, but we consider it here as a flat sequence (when its values are read according along its antidiagonals).
%C A374791 As a flat sequence, this is a permutation of the nonnegative integers with inverse A374792.
%H A374791 Rémy Sigrist, <a href="/A374791/b374791.txt">Table of n, a(n) for n = 0..8255</a>
%H A374791 Rémy Sigrist, <a href="/A374791/a374791.gp.txt">PARI program</a>
%H A374791 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%e A374791 Triangle T(n, k) begins:
%e A374791   n   n-th row
%e A374791   --  ------------------------------
%e A374791    0  0
%e A374791    1  1, 2
%e A374791    2  4
%e A374791    3  3, 5
%e A374791    4  6, 7, 8, 9
%e A374791    5  11, 13
%e A374791    6  12
%e A374791    7  17, 18
%e A374791    8  24
%e A374791    9  10, 14
%e A374791   10  15, 16, 19, 20
%e A374791   11  22, 26
%e A374791   12  21, 23, 25, 27
%e A374791   13  28, 29, 30, 31, 32, 33, 34, 35
%e A374791   14  37, 39, 41, 43
%e A374791   15  38, 42
%o A374791 (PARI) \\ See Links section.
%Y A374791 Cf. A120880, A374560, A374792 (inverse).
%K A374791 nonn,tabf,base
%O A374791 0,3
%A A374791 _Rémy Sigrist_, Jul 20 2024