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A069559
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Triangular numbers in which the k-th significant digit either divides k or is a multiple of k.
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2
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1, 3, 6, 15, 21, 28, 45, 66, 325, 666, 946, 1128, 1326, 2145, 2346, 2628, 2926, 4186, 8128, 8385, 8646, 8911, 11325, 11628, 14365, 18145, 18915, 51681, 52326, 54615, 54946, 58311, 111628, 118341, 152628, 214185, 258121, 614386, 1152921, 1211346
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OFFSET
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0,2
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COMMENTS
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If the smallest prime divisor of n is > 7 then the n-th digit is 1.
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LINKS
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EXAMPLE
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8646 is a member in which the fourth digit is 8 a multiple of 4, the third one is 6 a multiple of 3, the second one is 4 a multiple of 2 and the least significant digit is 6.
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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