A260300 Bisection of A258409: a(n) = A258409(2n+1).

2, 4, 6, 2, 10, 12, 2, 16, 18, 2, 22, 4, 2, 28, 30, 2, 2, 36, 2, 40, 42, 2, 46, 6, 2, 52, 2, 2, 58, 60, 2, 4, 66, 2, 70, 72, 2, 2, 78, 2, 82, 4, 2, 88, 6, 2, 2, 96, 2, 100, 102, 2, 106, 108, 2, 112, 2, 2, 2, 10, 2, 4, 126, 2, 130, 6, 2, 136, 138, 2, 2, 4, 2, 148, 150

Offset: 1

Author

Michel Marcus, Nov 10 2015

Keywords

• nonn

Crossrefs

Cf. A258409.

Programs

PARI

a(n) = gcd(apply(x->x-1, divisors(2*n+1)));