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A090094 a(n) is the smallest composite number coprime to n, n+1, n+2, n+3 and n+4. 3
49, 49, 121, 121, 121, 121, 169, 49, 49, 289, 289, 121, 121, 121, 49, 49, 121, 169, 169, 169, 169, 49, 49, 121, 121, 121, 121, 121, 49, 49, 169, 169, 169, 121, 121, 49, 49, 121, 121, 169, 169, 169, 49, 49, 121, 121, 121, 121, 121, 49, 49, 289, 169, 169, 169, 121, 49 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = A053673(n)^2.
MATHEMATICA
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]&&!PrimeQ[n]&&!Equal[n, 1]&&Equal[fla, 1], m=m+1; Print[n]; fla=0], {n, 1, 1000}], {k, 1, 256}]
scn[n_]:=Module[{cn=4}, While[!CompositeQ[cn]||!And@@CoprimeQ[ Range[ n, n+4], cn], cn++]; cn]; Array[scn, 60] (* Harvey P. Dale, Aug 12 2014 *)
CROSSREFS
Sequence in context: A221202 A291480 A255426 * A198435 A165870 A266803
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 26 2003
STATUS
approved

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Last modified March 28 08:02 EDT 2024. Contains 371236 sequences. (Running on oeis4.)