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A369097
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Least starting prime of exactly n consecutive primes p_i (i = 1..n) such that bigomega(p_i + 1) = 1 + i.
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3
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1) = 3, because bigomega(3+1) = 2 and no lesser number has this property.
a(2) = 5, because bigomega(5+1) = 2 and bigomega(7+1) = 3, and no lesser number has this property.
a(3) = 541, because bigomega(541+1) = 2, bigomega(547+1) = 3, bigomega(557+1) = 4 and no lesser number has this property.
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PROG
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(PARI) isok(p, n) = if (bigomega(p+1) != 2, return(0)); for (i=1, n-1, p = nextprime(p+1); if (bigomega(p+1) != i+2, return(0))); if (bigomega(nextprime(p+1)+1) == n+2, return(0)); return(1);
a(n) = my(p=2); while (!isok(p, n), p = nextprime(p+1)); p; \\ Michel Marcus, Jun 07 2024
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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