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A051318
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Euclid-Mullin sequence (A000945) with initial value a(1)=43 instead of a(1)=2.
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1
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43, 2, 3, 7, 13, 53, 5, 6221671, 38709183810571, 139, 2801, 11, 17, 5471, 52662739, 23003, 30693651606209, 37, 1741, 1313797957, 887, 71, 7127, 109, 23, 97, 159227, 643679794963466223081509857, 103, 1079990819, 9539, 3143065813, 29, 3847, 89, 19, 577, 223
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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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Product of first 28 terms +1 is 210102491806660945690525037461258737117339882568590700172677987135969766432980375 44232424110733238484973548134278212304532631, which is divisible by 103. Hence a(29)=103.
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MATHEMATICA
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a[1]=43; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, n-1} ] ] ] ]; Array[a, 15]
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PROG
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(PARI) spf(n)=factor(n)[1, 1]
first(m)={my(v=vector(m), i, t=43); v[1]=43; for(i=2, m, v[i]=spf(t+1); t*=v[i]; ); v; } /* Anders Hellström, Jul 19 2015 */
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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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