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 A274454 Products of distinct numbers in the Pell sequence (A000129). 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Clark Kimberling, Table of n, a(n) for n = 1..10000 EXAMPLE 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,...). MATHEMATICA 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}]; Take[s, 2 z]  (* A274454 *) CROSSREFS Cf. A160009, A274280. Sequence in context: A080792 A182656 A090050 * A192539 A046462 A188025 Adjacent sequences:  A274451 A274452 A274453 * A274455 A274456 A274457 KEYWORD nonn,easy AUTHOR Clark Kimberling, Jun 23 2016 STATUS approved

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Last modified July 30 02:28 EDT 2021. Contains 346346 sequences. (Running on oeis4.)