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Irregular triangle T(n, k), n > 0, k = 1..A067399(n), read by rows; the n-th row gives, in ascending order, the distinct integers k such that A067138(k, m) = n for some m.
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%I #11 Oct 09 2021 06:30:27

%S 1,1,2,1,3,1,2,4,1,5,1,2,3,6,1,3,7,1,2,4,8,1,9,1,2,5,10,1,11,1,2,3,4,

%T 6,12,1,13,1,2,3,6,7,14,1,3,5,7,15,1,2,4,8,16,1,17,1,2,9,18,1,19,1,2,

%U 4,5,10,20,1,5,21,1,2,11,22,1,23,1,2,3,4,6,8,12,24

%N Irregular triangle T(n, k), n > 0, k = 1..A067399(n), read by rows; the n-th row gives, in ascending order, the distinct integers k such that A067138(k, m) = n for some m.

%C The n-th row corresponds to the divisors of n in OR-numbral arithmetic.

%H Rémy Sigrist, <a href="/A348135/b348135.txt">Table of n, a(n) for n = 1..7412</a> (first 1024 rows flattened)

%H Rémy Sigrist, <a href="/A348135/a348135.gp.txt">PARI program for A348135</a>

%H <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a>

%F T(n, 1) = 1.

%F T(n, A067399(n)) = n.

%e The triangle starts:

%e 1: [1]

%e 2: [1, 2]

%e 3: [1, 3]

%e 4: [1, 2, 4]

%e 5: [1, 5]

%e 6: [1, 2, 3, 6]

%e 7: [1, 3, 7]

%e 8: [1, 2, 4, 8]

%e 9: [1, 9]

%e 10: [1, 2, 5, 10]

%e 11: [1, 11]

%e 12: [1, 2, 3, 4, 6, 12]

%e 13: [1, 13]

%e 14: [1, 2, 3, 6, 7, 14]

%e 15: [1, 3, 5, 7, 15]

%e 16: [1, 2, 4, 8, 16]

%o (PARI) See Links section.

%Y Cf. A067138, A067399, A346795.

%K nonn,tabf

%O 1,3

%A _Rémy Sigrist_, Oct 02 2021