A051311 Euclid-Mullin sequence (A000945) with initial value a(1)=17 instead of a(1)=2.

17, 2, 5, 3, 7, 3571, 31, 395202571, 13, 29, 137, 23, 97, 1896893, 34138453466895150823580146142491, 4639, 61, 181, 43, 19, 11, 59, 25292522503108044617, 4909, 18305191, 467

Offset: 1

Author

Labos Elemer

Keywords

• nonn

Links

• Robert Price, Table of n, a(n) for n = 1..30

Crossrefs

Cf. A000945, A000946, A005265, A005266.

Programs

Mathematica

a[1]=17; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, 1, n-1} ] ] ] ]; Array[a, 10]

PARI

spf(n)=factor(n)[1,1]
first(m)=my(v=vector(m)); v[1]=17; for(i=2, m, v[i]=spf(1+prod(j=1, i-1, v[j]))); v; \\ Anders Hellström, Aug 22 2015