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A194360
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Triangle of divisors of 105^n, each number occurring once.
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1
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1, 3, 5, 7, 15, 21, 35, 105, 9, 25, 45, 49, 63, 75, 147, 175, 225, 245, 315, 441, 525, 735, 1225, 1575, 2205, 3675, 11025, 27, 125, 135, 189, 343, 375, 675, 875, 945, 1029, 1125, 1323, 1715, 2625, 3087, 3375, 4725, 5145, 6125, 6615, 7875, 8575, 9261, 15435
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OFFSET
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0,2
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COMMENTS
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The length of row k is A003215(k), the centered hexagonal numbers, 3k^2 + 3k + 1.
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LINKS
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EXAMPLE
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The triangle has rows beginning with 3^k and ending with 105^k:
1
3, 5, 7, 15, 21, 35, 105
9, 25, 45, 49, 63, 75, 147, 175, 225, 245, 315, 441, 525, 735, 1225, 1575, 2205, 3675, 11025
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MATHEMATICA
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Join[{{1}}, Table[Complement[Divisors[105^n], Divisors[105^(n-1)]], {n, 9}]]
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CROSSREFS
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Cf. A108347 (numbers of the form (3^i)*(5^j)*(7^k))
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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