A080431 Even numbers such that all a(i)*a(j) are distinct.

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

Offset: 1

Author

Amarnath Murthy, Feb 20 2003

Keywords

• nonn

Crossrefs

Cf. A080430, A080432.

Equals 2*A066724.

Programs

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 Sellers, Feb 26 2003

Extensions

More terms from James Sellers, Feb 26 2003