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%I #15 Mar 24 2021 17:42:51
%S 2,2,6,4,20,6,14,16,18,20,22,12,52,14,30,16,34,18,38,20,42,22,92,72,
%T 150,52,54,56,58,30,186,32,66,34,70,36,222,38,78,40,164,42,86,88,90,
%U 92,94,96,196,150,102,52,106,54,110,56,114,58,236,60,366,186,252,128,130,66
%N Smallest multiple of n sandwiched between two squarefree numbers.
%H Amiram Eldar, <a href="/A085050/b085050.txt">Table of n, a(n) for n = 1..10000</a>
%t PrimeExponents[n_] := Flatten[ Table[ # [[2]], {1}] & /@ FactorInteger[n]]; f[n_] := Block[{k = 1}, While[ Union[ PrimeExponents[k*n - 1]] != {1} || Union[ PrimeExponents[k*n + 1]] != {1}, k++ ]; k*n]; Table[ f[n], {n, 2, 70}]
%t smn[n_]:=Module[{c=1},While[!SquareFreeQ[c*n-1]||!SquareFreeQ[c*n+1],c++];c*n]; Array[smn,70] (* _Harvey P. Dale_, Mar 24 2021 *)
%Y Cf. A005117.
%K easy,nonn
%O 1,1
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 20 2003
%E Edited and extended by _Robert G. Wilson v_, Jun 27 2003
%E a(1)-a(2) corrected by _Amiram Eldar_, Feb 24 2021
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