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Euclid-Mullin sequence (A000945) with initial value a(1)=11 instead of a(1)=2.
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%I #22 Jan 13 2024 11:47:00

%S 11,2,23,3,7,10627,433,17,13,10805892983887,73,6397,19,489407,2753,

%T 87491,18618443,5,31,113,41,10723,35101153,25243,374399,966011,

%U 293821591198219762366057,234947,4729,27953,3256171,331,613,67,272646324430637,34281113,21050393332691947013,61,97

%N Euclid-Mullin sequence (A000945) with initial value a(1)=11 instead of a(1)=2.

%H A. R. Booker and S. A. Irvine, <a href="http://arxiv.org/abs/1508.03039">The Euclid-Mullin graph</a>, arXiv preprint arXiv:1508.03039 [math.NT], 2015-2016.

%t a[1]=11; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, 1, n-1} ] ] ] ]; Array[a,10]

%o (PARI) lpf(n)=factor(n)[1,1]

%o first(m)=my(v=vector(m)); v[1]=11; for(i=2, m, v[i]=lpf(1+prod(j=1, i-1, v[j]))); v;

%o \\ _Anders Hellström_, Aug 22 2015

%Y Cf. A000945, A000946, A005265, A005266.

%K nonn

%O 1,1

%A _Labos Elemer_

%E Corrected and extended by _Sean A. Irvine_, Apr 13 2008