

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
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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



