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Irregular triangle read by rows: row(n) consists of the first A011764(n-1) terms of A006047.
1

%I #13 May 12 2023 09:07:51

%S 1,2,3,1,2,3,2,4,6,3,6,9,1,2,3,2,4,6,3,6,9,2,4,6,4,8,12,6,12,18,3,6,9,

%T 6,12,18,9,18,27,2,4,6,4,8,12,6,12,18,4,8,12,8,16,24,12,24,36,6,12,18,

%U 12,24,36,18,36,54,3,6,9,6,12,18,9,18,27,6,12,18,12,24,36,18,36,54,9,18,27

%N Irregular triangle read by rows: row(n) consists of the first A011764(n-1) terms of A006047.

%e Triangle begins:

%e {1, 2, 3},

%e {1, 2, 3, 2, 4, 6, 3, 6, 9},

%e {1, 2, 3, 2, 4, 6, 3, 6, 9, 2, 4, 6, 4, 8, 12, 6, 12, 18, 3, 6, 9, 6, 12, 18, 9, 18, 27, 2, 4, 6, 4, 8, 12, 6, 12, 18, 4, 8, 12, 8, 16, 24, 12, 24, 36, 6, 12, 18, 12, 24, 36, 18, 36, 54, 3, 6, 9, 6, 12, 18, 9, 18, 27, 6, 12, 18, 12, 24, 36, 18, 36, 54, 9, 18, 27, 18, 36, 54, 27, 54, 81}, ...

%Y Cf. A011764, A115245, A130831.

%K nonn,less,tabf

%O 1,2

%A _Roger L. Bagula_, Aug 20 2007

%E Edited by _N. J. A. Sloane_, Jun 07 2008