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A337471
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Primorial inflation of n prime shifted once: a(n) = A003961(A108951(n)).
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2
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1, 3, 15, 9, 105, 45, 1155, 27, 225, 315, 15015, 135, 255255, 3465, 1575, 81, 4849845, 675, 111546435, 945, 17325, 45045, 3234846615, 405, 11025, 765765, 3375, 10395, 100280245065, 4725, 3710369067405, 243, 225225, 14549535, 121275, 2025, 152125131763605, 334639305, 3828825, 2835, 6541380665835015, 51975, 307444891294245705, 135135
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OFFSET
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1,2
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LINKS
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FORMULA
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Sum_{n>=1} 1/a(n) = 1 / Product_{k>=2} (1 - 1/A070826(k)) = 1.6241170949... . - Amiram Eldar, Dec 08 2022
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PROG
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(PARI)
A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f);
A034386(n) = prod(i=1, primepi(n), prime(i));
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CROSSREFS
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KEYWORD
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nonn,mult
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AUTHOR
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STATUS
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approved
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