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A160966
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Starting from a(1)=2, a(n) = A028260(1+a(n-1)) if n is even, a(n) = A026424(a(n-1)) if n is odd.
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2, 6, 11, 25, 45, 94, 176, 361, 700, 1405, 2752, 5533, 10964, 22011, 43839, 87868, 175557, 351746, 703243, 1407705, 2814709, 5631461, 11261009, 22524901, 45044446, 90091251, 180165450, 360333977, 720640449, 1441293048, 2882532607
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| If a(1) were set to 3, the equivalent sequence would start 3, 9, 17, 38, 71, 146, 279,...
Alternatively starting from a(1)=4 we get 4, 10, 18, 39, 72, 150,..
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EXAMPLE
| a(2)= 6, the second integer containing an even number of prime factors.
a(3)= 11, the sixth integer containing an odd number of primes.
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CROSSREFS
| Cf. A141436
Sequence in context: A067605 A072986 A079047 * A052326 A079118 A034466
Adjacent sequences: A160963 A160964 A160965 * A160967 A160968 A160969
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KEYWORD
| nonn
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AUTHOR
| Daniel Tisdale (daniel6874(AT)gmail.com), May 31 2009
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EXTENSIONS
| Definition clarified, sequence extended beyond 25 by R. J. mathar (mathar(AT)strw.leidenuniv.nl), May 31 2010
a(15)-a(31) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jul 02 2010
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