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A090095 a(n) is the smallest composite number coprime to n, n+1, n+2, n+3, n+4 and n+5. 1
49, 121, 121, 121, 121, 169, 169, 49, 289, 289, 289, 121, 121, 121, 49, 121, 169, 169, 169, 169, 289, 49, 121, 121, 121, 121, 121, 169, 49, 169, 169, 169, 169, 121, 121, 49, 121, 121, 289, 169, 169, 169, 49, 169, 121, 121, 121, 121, 121, 49, 361, 289, 169, 169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

FORMULA

a(n)=A053674[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]&&Equal[s5, 1]&&!PrimeQ[n]&&!Equal[n, 1]&&Equal[fla, 1], m=m+1; Print[n]; fla=0], {n, 1, 1000}], {k, 1, 256}]

CROSSREFS

Cf. A053669-A053674, A090090-A090094.

Sequence in context: A044236 A044617 A216169 * A163245 A084733 A227863

Adjacent sequences:  A090092 A090093 A090094 * A090096 A090097 A090098

KEYWORD

nonn

AUTHOR

Labos Elemer, Nov 26 2003

STATUS

approved

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Last modified September 18 11:42 EDT 2018. Contains 315130 sequences. (Running on oeis4.)