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%I #14 Jul 30 2020 20:31:27
%S 49,121,121,121,121,169,169,49,289,289,289,121,121,121,49,121,169,169,
%T 169,169,289,49,121,121,121,121,121,169,49,169,169,169,169,121,121,49,
%U 121,121,289,169,169,169,49,169,121,121,121,121,121,49,361,289,169,169
%N a(n) is the smallest composite number coprime to n, n+1, n+2, n+3, n+4 and n+5.
%H Harvey P. Dale, <a href="/A090095/b090095.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A053674(n)^2.
%t m=0;Table[fla=1;Do[s=GCD[n, k];s1=GCD[n, k+1]; s2=GCD[n, k+2];s3=GCD[n, k+3];s4=GCD[n, k+4];s5=GCD[n, k+5]; If[Equal[s, 1]&&Equal[s1, 1]&&Equal[s2, 1]&&Equal[s3, 1]&& Equal[s4, 1]&&Equal[s5, 1]&&!PrimeQ[n]&&!Equal[n, 1]&&Equal[fla, 1], m=m+1;Print[n];fla=0], {n, 1, 1000}], {k, 1, 256}]
%t scn[n_]:=Module[{k=4,c=n+Range[0,5]},While[PrimeQ[k]||!AllTrue[c,CoprimeQ[ k,#]&],k++];k]; Array[scn,60] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 30 2020 *)
%Y Cf. A053669, A053670, A053671, A053672, A053673, A053674.
%Y Cf. A090092, A090093, A090094.
%K nonn
%O 1,1
%A _Labos Elemer_, Nov 26 2003
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