A275664 a(n) is the sum of the LCM and GCD of all previous terms, with a(0) = 2.

2, 4, 6, 14, 86, 3614, 6526886, 21300113901614, 226847426110843688722000886, 25729877366557343481074291996721923093306518970391614

Offset: 0

Author

Andres Cicuttin, Aug 04 2016

Keywords

• nonn

Comments

Starting from 1, instead of from 2, it is generated A129871 (A variant of Sylvester's sequence A000058).

Links

• Andres Cicuttin, Table of n, a(n) for n = 0..13

Crossrefs

Cf. A129871, A000058.

Programs

Mathematica

a = {2}; Do[AppendTo[a, LCM @@ a + GCD @@ a], {i, 1, 10}]; Column[a]

Formula

a(0) = 2, a(n+1) = lcm(a(0),a(1),..,a(n)) + gcd(a(0),a(1),..,a(n)).