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A374817 Irregular table T(n, k), n > 0, k = 1..A000005(n), read by rows; the n-th row lists the numbers m such that A003991(m) = n.

%I A374817 #11 Jul 22 2024 14:24:05
%S A374817 1,2,3,4,6,5,7,10,11,15,8,9,16,21,22,28,12,14,29,36,13,37,45,17,20,46,
%T A374817 55,56,66,18,19,23,27,67,78,79,91,30,35,92,105,24,26,106,120,25,38,44,
%U A374817 121,136,137,153,31,34,47,54,154,171,172,190,32,33,57,65,191,210
%N A374817 Irregular table T(n, k), n > 0, k = 1..A000005(n), read by rows; the n-th row lists the numbers m such that A003991(m) = n.
%C A374817 A003991 corresponds to a square array, but we consider it here as a flat sequence (when its values are read according along its antidiagonals).
%C A374817 This sequence is a permutation of the positive integers with inverse A374818.
%H A374817 Rémy Sigrist, <a href="/A374817/b374817.txt">Table of n, a(n) for n = 1..7069</a> (rows for n = 1..1000 flattened)
%H A374817 Rémy Sigrist, <a href="/A374817/a374817.gp.txt">PARI program</a>
%H A374817 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A374817 T(n, A000005(n)) = A000217(n).
%e A374817 Table T(n, k) begins:
%e A374817   n   n-th row
%e A374817   --  ----------------------
%e A374817    1  1
%e A374817    2  2, 3
%e A374817    3  4, 6
%e A374817    4  5, 7, 10
%e A374817    5  11, 15
%e A374817    6  8, 9, 16, 21
%e A374817    7  22, 28
%e A374817    8  12, 14, 29, 36
%e A374817    9  13, 37, 45
%e A374817   10  17, 20, 46, 55
%e A374817   11  56, 66
%e A374817   12  18, 19, 23, 27, 67, 78
%e A374817   13  79, 91
%e A374817   14  30, 35, 92, 105
%e A374817   15  24, 26, 106, 120
%o A374817 (PARI) \\ See Links section.
%Y A374817 See A374799 for a similar sequence.
%Y A374817 Cf. A000005, A000217, A003991, A374818 (inverse).
%K A374817 nonn,tabf
%O A374817 1,2
%A A374817 _Rémy Sigrist_, Jul 21 2024