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A043547
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Odd numbers in sequence interspersed with double the previous odd number.
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3
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1, 2, 3, 6, 5, 10, 7, 14, 9, 18, 11, 22, 13, 26, 15, 30, 17, 34, 19, 38, 21, 42, 23, 46, 25, 50, 27, 54, 29, 58, 31, 62, 33, 66, 35, 70, 37, 74, 39, 78, 41, 82, 43, 86, 45, 90, 47, 94, 49, 98, 51, 102, 53, 106, 55, 110, 57, 114, 59, 118, 61, 122, 63, 126, 65, 130, 67, 134
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = (2 - n) * (n - [n / 2] * 2) + 2 * (n - 1)
G.f. x(1+2x)(1+x^2)/(1-x^2)^2. - Ralf Stephan, Jun 10 2003
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EXAMPLE
| E.g. a(1)=1 because n is odd. a(2)=2 because a(1)*2=2
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CROSSREFS
| For n>3, a(n) = A059029(n-3)+3. For n>1, a(n) = A022998(n-2)+2.
Sequence in context: A080029 A091239 A145110 * A064919 A064923 A064924
Adjacent sequences: A043544 A043545 A043546 * A043548 A043549 A043550
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KEYWORD
| easy,nonn
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AUTHOR
| Jim Cook (jcook(AT)halcyon.com), Mar 01 2000
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EXTENSIONS
| More terms from James A. Sellers (sellersj(AT)math.psu.edu), Mar 01 2000
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