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A067042
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Numbers in which the product of digits in even positions = product of digits in odd positions.
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1
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11, 22, 33, 44, 55, 66, 77, 88, 99, 100, 111, 122, 133, 144, 155, 166, 177, 188, 199, 200, 221, 242, 263, 284, 300, 331, 362, 393, 400, 441, 482, 500, 551, 600, 661, 700, 771, 800, 881, 900, 991, 1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007, 1008, 1009
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..51.
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FORMULA
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Asymptotics: For any n, let f(n) be the number of entries in this sequence that are less than n. Then f(n)/n approaches 1 as n goes to infinity. This is because among numbers with a large number of digits, almost all have 0's in both odd positions and even positions. - David Wasserman, Jan 16 2002
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EXAMPLE
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2364 is a member as 2*6 = 3*4.
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CROSSREFS
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Sequence in context: A033283 A044851 A160861 * A078273 A065571 A064544
Adjacent sequences: A067039 A067040 A067041 * A067043 A067044 A067045
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KEYWORD
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base,nonn,easy
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Dec 29 2001
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EXTENSIONS
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Corrected by David Wasserman, Jan 16 2002
More terms from Sascha Kurz, Mar 23 2002
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STATUS
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approved
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