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A274454
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Products of distinct numbers in the Pell sequence (A000129).
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1
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2, 5, 10, 12, 24, 29, 58, 60, 70, 120, 140, 145, 169, 290, 338, 348, 350, 408, 696, 700, 816, 840, 845, 985, 1680, 1690, 1740, 1970, 2028, 2030, 2040, 2378, 3480, 4056, 4060, 4080, 4200, 4756, 4896, 4901, 4925, 5741, 8400, 9792, 9802, 9850, 10140, 10150
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OFFSET
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1,1
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LINKS
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EXAMPLE
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The numbers in A274454 are 1, 2, 5, 12, 29, 70, 169, 408,..., so that the sequence of all products of distinct members, in increasing order, is (2, 5, 10, 12, 24, 29, 58, 60,...).
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MATHEMATICA
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r[1] = 1; r[2] = 2; r[n_] := r[n] = 2 r[n - 1] + r[n - 2]
s = {1}; z = 30; f = Map[r, Range[z]]; Take[f, 20] (* A000129 *)
Do[s = Union[s, Select[s*f[[i]], # <= f[[z]] &]], {i, z}];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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