A051309 Euclid-Mullin sequence (A000945) with initial value a(1)=11 instead of a(1)=2.

11, 2, 23, 3, 7, 10627, 433, 17, 13, 10805892983887, 73, 6397, 19, 489407, 2753, 87491, 18618443, 5, 31, 113, 41, 10723, 35101153, 25243, 374399, 966011, 293821591198219762366057, 234947, 4729, 27953, 3256171, 331, 613, 67, 272646324430637, 34281113, 21050393332691947013, 61, 97

Offset: 1

Author

Labos Elemer

Keywords

• nonn

Links

• A. R. Booker and S. A. Irvine, The Euclid-Mullin graph, arXiv preprint arXiv:1508.03039 [math.NT], 2015-2016.

Crossrefs

Cf. A000945, A000946, A005265, A005266.

Programs

Mathematica

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

PARI

lpf(n)=factor(n)[1,1]
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;
\\ Anders Hellström, Aug 22 2015

Extensions

Corrected and extended by Sean A. Irvine, Apr 13 2008