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A293457
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Primes that divide the numerator of the sum of the reciprocals of all smaller primes.
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3
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OFFSET
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1,1
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COMMENTS
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Exhaustive search finds no more terms among the first 10^7 primes.
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LINKS
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FORMULA
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EXAMPLE
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Since 1/2 + 1/3 + 1/5 + 1/7 + 1/11 + 1/13 + 1/17 = 716167/510510 and 19 divides 716167, 19 is in the sequence.
Since there are no primes less than 2, the sum of their reciprocals is 0/1, and as 2 divides 0, it is therefore included as the first term of this sequence. - Antti Karttunen, Feb 08 2024
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PROG
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(PARI) lista(nn) = my(s = 0); forprime(p=2, nn, if (!(numerator(s) % p), print1(p, ", ")); s += 1/p; ); \\ Michel Marcus, Oct 09 2017, edited for the new, more inclusive definition by Antti Karttunen, Feb 08 2024
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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Relaxed the definition to include 2 as the first term - Antti Karttunen, Feb 08 2024
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STATUS
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approved
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