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A051313
Euclid-Mullin sequence (A000945) with initial value a(1)=23 instead of a(1)=2.
1
23, 2, 47, 3, 13, 84319, 7109609443, 463, 23403050994721829453179, 7, 5, 57367, 239, 40237, 10575444619218059847586376042094152838881224222904607376771, 31333, 742759, 9444637217
OFFSET
1,1
LINKS
MATHEMATICA
a[1]=23; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, 1, n-1} ] ] ] ]; Array[a, 10]
PROG
(PARI) spf(n)=factor(n)[1, 1]
first(m)=my(v=vector(m)); v[1]=23; for(i=2, m, v[i]=spf(1+prod(j=1, i-1, v[j]))); v; \\ Anders Hellström, Nov 22 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(18)-a(37) from Robert Price, Jul 17 2015
STATUS
approved