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A077129
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Smallest number which is relatively prime to all the numbers between successive odd primes.
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2
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3, 5, 7, 5, 11, 5, 13, 11, 7, 13, 7, 5, 7, 11, 13, 7, 17, 11, 5, 17, 7, 13, 11, 13, 5, 11, 5, 13, 37, 7, 13, 5, 17, 7, 23, 11, 7, 11, 13, 7, 29, 5, 11, 5, 31, 19, 11, 5, 13, 11, 7, 17, 13, 11, 13, 7, 19, 11, 5, 23, 29, 13, 5, 11, 31, 11, 29, 5, 17, 11, 17, 11, 19, 7, 13, 19, 11
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OFFSET
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0,1
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COMMENTS
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Naturally every member is a prime.
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LINKS
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EXAMPLE
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a(5)= 11,is the smallest number coprime to all the numbers from 13 to 17 i.e. 14,15 and 16.
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MATHEMATICA
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sncp[n_]:=Module[{cr=Range[Prime[n]+1, Prime[n+1]-1], k=3}, While[Total[Boole[CoprimeQ[ cr, k]]]!= Length[cr], k=NextPrime[k]]; k]; Array[sncp, 80, 2] (* Harvey P. Dale, Apr 06 2023 *)
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PROG
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(PARI) for(n=2, 100, for(i=2, 10^9, f=0:for(k=prime(n)+1, nextprime(prime(n)+1)-1, if(gcd(i, k)>1, f=1:break)): if(!f, print1(i", "):break)))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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