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A158302
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"1" followed by repeats of 2^k deleting all 4^k, k>0
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1
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1, 2, 2, 8, 8, 32, 32, 128, 128, 512, 512, 2048, 2048, 8192, 8192, 32768, 32768
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Binomial transform = A122983: (1, 3, 7, 21, 61, 183,...). Equals right border of triangle A158301.
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FORMULA
| 1 followed by repeats of powers of 2, deleting powers of 4: (4, 16, 64,...). Inverse binomial transform of A122983 starting (1, 3, 7, 21, 61, 183,...).
For n > 3: a(n) = a(n-1)*a(n-2)/a(n-3). [Reinhard Zumkeller, Mar 06 2011]
For n > 3: a(n) = 4a(n-2). [Charles R Greathouse IV, Feb 06 2011]
a(n) = Sum_{k, 0<=k<=n} A154388(n,k)*2^k. - DELEHAM Philippe, Dec 17 2011
G.f.: (1+2*x-2*x^2)/(1-4*x^2). - DELEHAM Philippe, Dec 17 2011
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EXAMPLE
| Given "1" followed by repeats of powers of 2: (1, 2, 2, 4, 4, 8, 8, 16, 16,...);
delete powers of 4: (4, 16, 64, 156,...) leaving A158300:
(1, 2, 2, 8, 8, 32, 32, 128, 128,...).
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CROSSREFS
| Cf. A122983, A158301, A154388
Sequence in context: A120544 A155950 A162959 * A007083 A144060 A016119
Adjacent sequences: A158299 A158300 A158301 * A158303 A158304 A158305
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KEYWORD
| nonn,easy
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AUTHOR
| Gary W. Adamson (qntmpkt(AT)yahoo.com), Mar 15 2009
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