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