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 A080429 Odd numbers such that all a(i)*a(j) with i
 1, 3, 5, 7, 9, 11, 13, 17, 19, 23, 25, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67, 71, 73, 79, 81, 83, 89, 97, 101, 103, 105, 107, 109, 113, 121, 127, 131, 137, 139, 149, 151, 157, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE 49 belongs to this sequence but 45 does not as 45*1 = 9*5. MAPLE S := {3}: A := array(1..10^3): for m from 1 to 10^3 do A[m] := 0 od: A[1] := 1: A[3] := 3: for n from 5 to 10^3-1 by 2 do mytest := 0: for j from 1 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 1 to n-2 by 2 do S := S union {A[j]*n} od: fi: od: for i from 1 to 10^3-1 by 2 do if A[i]>0 then printf(`%d, `, A[i]) fi: od: # James A. Sellers, Feb 25 2003 CROSSREFS Cf. A062090. Sequence in context: A061345 A238266 A308838 * A326581 A050150 A062090 Adjacent sequences:  A080426 A080427 A080428 * A080430 A080431 A080432 KEYWORD nonn AUTHOR Amarnath Murthy, Feb 20 2003 EXTENSIONS More terms from James A. Sellers, Feb 25 2003 STATUS approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)