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A306992
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Lexicographically earliest sequence of distinct positive terms such that the product of two consecutive terms is digitally balanced.
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2
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1, 2, 5, 7, 6, 25, 9, 15, 10, 17, 12, 13, 4, 3, 14, 11, 18, 31, 19, 29, 8, 23, 26, 22, 40, 63, 33, 69, 36, 67, 34, 21, 99, 27, 30, 82, 28, 81, 35, 61, 16, 47, 50, 53, 48, 73, 37, 20, 41, 56, 45, 49, 43, 52, 51, 42, 54, 46, 55, 44, 57, 38, 65, 127, 66, 135, 70
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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COMMENTS
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Digitally balanced numbers correspond to A031443.
This sequence has similarities with A269361.
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LINKS
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EXAMPLE
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The first terms, alongside the binary representation of a(n)*a(n+1), are:
n a(n) bin(a(n)*a(n+1))
-- ---- ----------------
1 1 10
2 2 1010
3 5 100011
4 7 101010
5 6 10010110
6 25 11100001
7 9 10000111
8 15 10010110
9 10 10101010
10 17 11001100
11 12 10011100
12 13 110100
13 4 1100
14 3 101010
15 14 10011010
16 11 11000110
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PROG
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(PARI) See Links section.
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CROSSREFS
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See A306994 for the additive variant.
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KEYWORD
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AUTHOR
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STATUS
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approved
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