A051331 Euclid-Mullin sequence (A000945) with initial value a(1)=131071 instead of a(1)=2.

131071, 2, 3, 43, 31, 113, 5, 13, 4391, 7, 8012161, 3090097, 17, 809, 83843, 18743, 29, 179, 2347, 83, 97883, 14411, 12109, 97, 25951, 5506100565736709510249607377685096261432096111292821492562747465234861171

Offset: 1

Author

Labos Elemer

Keywords

• easy
• nonn

Links

• Robert Price, Table of n, a(n) for n = 1..36

Crossrefs

Cf. A000945, A000946, A005265, A005266.

Programs

Mathematica

a[1]=131071; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, 1, n-1} ] ] ] ]; Array[a, 10]

PARI

gpf(n)=my(f=factor(n)[, 1]); f[#f];
first(m)=my(v=vector(m)); v[1]=131071; for(i=2, m, v[i]=gpf(1+prod(j=1, i-1, v[j]))); v \\ Anders Hellström, Nov 25 2015