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A308501
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Partial products of odious numbers.
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1
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1, 1, 2, 8, 56, 448, 4928, 64064, 896896, 14350336, 272656384, 5725784064, 125967249408, 3149181235200, 81878712115200, 2292603939225600, 71070722115993600, 2274263107711795200, 79599208769912832000, 2945170724486774784000, 111916487530497441792000, 4588575988750395113472000
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = Product_{k=1..n} A000069(k).
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MATHEMATICA
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Join[{1}, FoldList[Times, Select[Range[0, 50], OddQ[DigitCount[#, 2, 1]]&]]] (* Harvey P. Dale, Aug 09 2024 *)
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PROG
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(PARI) f(n) = 2*n - 1 - hammingweight(n-1)%2; \\ A000069
a(n) = prod(k=1, n, f(k))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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