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A119585
Triangle where n-th row is (1,2,3,...n) arranged first by number of divisors and then numerically (among those integers with the same number of divisors).
0
1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 5, 4, 1, 2, 3, 5, 4, 6, 1, 2, 3, 5, 7, 4, 6, 1, 2, 3, 5, 7, 4, 6, 8, 1, 2, 3, 5, 7, 4, 9, 6, 8, 1, 2, 3, 5, 7, 4, 9, 6, 8, 10, 1, 2, 3, 5, 7, 11, 4, 9, 6, 8, 10, 1, 2, 3, 5, 7, 11, 4, 9, 6, 8, 10, 12, 1, 2, 3, 5, 7, 11, 13, 4, 9, 6, 8, 10, 12
OFFSET
1,3
EXAMPLE
Looking at the 9th row, we want to arrange (1,2,3,4,5,6,7,8,9). 1 has 1 divisor.
(2,3,5,7) each have 2 divisors. (4,9) each have 3 divisors. (6,8) each have 4 divisors. So the 9th row is (1)(2,3,5,7)(4,9)(6,8).
CROSSREFS
Sequence in context: A222417 A253573 A229945 * A195097 A329288 A181845
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, May 31 2006
STATUS
approved