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A235590
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Sum of parts of the form 10...0 with nonnegative number of zeros in binary representation of c-squarefree numbers (A233564) as the corresponding powers of 2.
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0
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1, 2, 4, 3, 3, 8, 5, 5, 16, 9, 6, 6, 9, 32, 17, 10, 7, 7, 10, 7, 7, 17, 7, 7, 64, 33, 18, 12, 11, 11, 12, 18, 11, 11, 33, 11, 11, 128, 65, 34, 20, 19, 19, 13, 13, 20, 13, 13, 34, 19, 19, 65, 19, 13, 13, 19, 256, 129, 66, 36, 35
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OFFSET
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1,2
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COMMENTS
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The number of times of appearances of number k in the sequence is the number of compositions of k into distinct powers of 2, i.e., it is A000120(k)!
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LINKS
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FORMULA
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Let, for k_1>k_2>...>k_r, A233564(n) = 2^k_1 + 2^k_2 +...+ 2^k_r. Then a(n) = 2^(k_1-k_2-1) + 2^(k_2-k_3-1) + 2^(k_(r-1)-k_r-1) + 2^k_r.
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EXAMPLE
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Let n=17, A233564(17)=37. In binary a concatenation of parts of the form 10...0 which gives 37 is (100)(10)(1). Thus a(17)= 4+2+1 = 7.
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MATHEMATICA
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bitPatt[n_]:=bitPatt[n]=Split[IntegerDigits[n, 2], #2==0&]; Map[Plus@@(Map[FromDigits[#, 2]&, bitPatt[#]])&, Select[Range[300], #==DeleteDuplicates[#]&[bitPatt[#]]&]] (* Peter J. C. Moses, Jan 15 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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