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%I #23 Jan 13 2024 11:51:42
%S 13,2,3,79,6163,7,1601,11,137,5,199,151,263,983,31,83,30187890723499,
%T 23847817657,37,67,9661,251,73,1214623152057970133,
%U 24597089626521443731307390760915220105471840174452030562332559181845834101711082531
%N Euclid-Mullin sequence (A000945) with initial value a(1)=13 instead of a(1)=2.
%H Robert Price, <a href="/A051310/b051310.txt">Table of n, a(n) for n = 1..36</a>
%H A. R. Booker, 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]=13; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, 1, n-1} ] ] ] ]; Array[a, 10]
%o (PARI) spf(n)=factor(n)[1,1]
%o first(m)=my(v=vector(m)); v[1]=13; for(i=2, m, v[i]=spf(1+prod(j=1, i-1, v[j]))); v; \\ _Anders Hellström_, Aug 22 2015
%Y Cf. A000945, A000946, A005265, A005266.
%K nonn
%O 1,1
%A _Labos Elemer_