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A331010 Lexicographically earliest sequence of distinct positive terms that can be viewed as an irregular table where the n-th row has A000005(a(n)) terms and T(n, k) is a multiple of the k-th divisor of a(n) (=A027750(a(n), k)).

%I A331010 #17 Jan 09 2020 18:30:13
%S A331010 1,2,4,3,6,8,5,9,7,10,12,18,11,14,16,24,13,15,17,21,27,19,28,20,22,25,
%T A331010 30,23,26,33,32,36,48,29,34,39,42,45,54,31,44,35,38,49,56,37,40,52,64,
%U A331010 80,41,46,51,60,66,72,84,96,43,65,47,57,50,75,53,68,55
%N A331010 Lexicographically earliest sequence of distinct positive terms that can be viewed as an irregular table where the n-th row has A000005(a(n)) terms and T(n, k) is a multiple of the k-th divisor of a(n) (=A027750(a(n), k)).
%C A331010 This sequence is a permutation of the natural numbers as each row starts with the least value not yet in the sequence.
%C A331010 The prime numbers appear in ascending order.
%H A331010 Rémy Sigrist, <a href="/A331010/b331010.txt">Table of n, a(n) for n = 1..10000</a>
%H A331010 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%H A331010 Rémy Sigrist, <a href="/A331010/a331010.gp.txt">PARI program for A331010</a>
%e A331010 The first terms and rows are:
%e A331010   n   a(n)  row(n)
%e A331010   --  ----  -------------------------
%e A331010    1     1  [1]
%e A331010    2     2  [2, 4]
%e A331010    3     4  [3, 6, 8]
%e A331010    4     3  [5, 9]
%e A331010    5     6  [7, 10, 12, 18]
%e A331010    6     8  [11, 14, 16, 24]
%e A331010    7     5  [13, 15]
%e A331010    8     9  [17, 21, 27]
%e A331010    9     7  [19, 28]
%e A331010   10    10  [20, 22, 25, 30]
%e A331010   11    12  [23, 26, 33, 32, 36, 48]
%e A331010   12    18  [29, 34, 39, 42, 45, 54]
%e A331010   13    11  [31, 44]
%e A331010   14    14  [35, 38, 49, 56]
%e A331010   15    16  [37, 40, 52, 64, 80]
%e A331010   16    24  [41, 46, 51, 60, 66, 72, 84, 96]
%o A331010 (PARI) See Links section.
%Y A331010 See A331016, A331018 and A331026 for similar sequences.
%Y A331010 Cf. A000005, A027750.
%K A331010 nonn,look,tabf
%O A331010 1,2
%A A331010 _Rémy Sigrist_, Jan 06 2020