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 A080431 Even numbers such that all a(i)*a(j) are distinct. 2
 2, 4, 6, 8, 10, 14, 18, 22, 26, 32, 34, 38, 46, 50, 58, 60, 62, 74, 82, 86, 94, 98, 106, 118, 122, 134, 142, 146, 158, 162, 166, 168, 178, 194, 202, 206, 214, 218, 226, 242, 254, 256, 262, 274, 278, 298, 302, 308, 314, 326, 334, 338, 346, 358, 360, 362, 382, 386 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MAPLE S := {8}: A := array(1..10^3): for m from 1 to 10^3 do A[m] := 0 od: A[2] := 2: A[4] := 4: for n from 6 to 10^3 by 2 do mytest := 0: for j from 2 to n-2 by 2 do if A[j]>0 then if member(A[j]*n, S) then mytest := 1; break; fi: fi: od: if mytest=0 then A[n] := n; for j from 2 to n-2 by 2 do S := S union {A[j]*n} od: fi: od: for i from 2 to 10^3 by 2 do if A[i]>0 then printf(`%d, `, A[i]) fi: od: # James A. Sellers, Feb 26 2003 CROSSREFS Cf. A080430, A080432. Equals 2*A066724. Sequence in context: A151566 A160406 A113293 * A288732 A122642 A305703 Adjacent sequences:  A080428 A080429 A080430 * A080432 A080433 A080434 KEYWORD nonn AUTHOR Amarnath Murthy, Feb 20 2003 EXTENSIONS More terms from James A. Sellers, Feb 26 2003 STATUS approved

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Last modified September 24 07:28 EDT 2020. Contains 337317 sequences. (Running on oeis4.)