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A102377
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Gould's sequence A001316 in binary.
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0
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1, 10, 10, 100, 10, 100, 100, 1000, 10, 100, 100, 1000, 100, 1000, 1000, 10000, 10, 100, 100, 1000, 100, 1000, 1000, 10000, 100, 1000, 1000, 10000, 1000, 10000, 10000, 100000, 10, 100, 100, 1000, 100, 1000, 1000, 10000, 100, 1000, 1000, 10000, 1000
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,2
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LINKS
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FORMULA
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Formulas due to Paul D. Hanna:
a(n) = Product_{k=0..log_2(n)} 10^b(n,k) where b(n,k) = coefficient of 2^k in binary expansion of n.
a(n) = Sum_{k=0..n} (C(n,k) mod 2)*9^A000120(n-k).
G.f.: Product_{k>=0} 1 + 10*x^(2^k).
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PROG
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(PARI) a(n) = 10^hammingweight(n); \\ Kevin Ryde, Jan 11 2024
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CROSSREFS
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KEYWORD
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easy,base,nonn
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AUTHOR
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STATUS
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approved
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