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A090886
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Primes in the products of consecutive prime-indexed primes + 2 or A080696(n) + 2.
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0
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OFFSET
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1,1
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COMMENTS
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These numbers, except for the first one, always end in 7.
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LINKS
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MATHEMATICA
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Select[FoldList[Times, Table[Prime[n], {n, Prime[Range[40]]}]]+2, PrimeQ] (* Harvey P. Dale, Apr 05 2019 *)
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PROG
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(PARI) piptorial2(n) = { y=1; for(x=1, n, v=prime(prime(x)); y*=v; if(isprime(y+2), print1(y+2", ")) ) }
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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