A119250 Smallest number greater than n having a maximal number of divisors d such that d-1 are divisors of n.

2, 6, 4, 6, 6, 12, 8, 30, 20, 66, 12, 60, 14, 24, 48, 30, 18, 84, 20, 30, 88, 276, 24, 60, 78, 42, 140, 30, 30, 84, 32, 90, 204, 630, 72, 60, 38, 60, 280, 90, 42, 84, 44, 60, 60, 1128, 48, 60, 200, 66, 468, 210, 54, 84, 168, 120, 580, 1770, 60, 420, 62, 96, 440, 90, 462, 84

Offset

1,1

Comments

Let x(0)=1 and x(k) = lcm(x(k-1), d(k)) with 1 <= k <= A000005(n), where d(k) = (k-th divisor of n): A057643(n)=x(A000005(n)) and a(n) = Min{x(i): x(i)>n}.

a(n) = n+1 iff n is an odd prime;

A057643(n) = x(A000005(n)) and a(n) = Min{x(i): x(i)>n}.

Links

Table of n, a(n) for n=1..66.

Crossrefs

Cf. A027750.

Sequence in context: A319376 A110633 A240232 * A059773 A127399 A240751

Adjacent sequences: A119247 A119248 A119249 * A119251 A119252 A119253

Keyword

nonn

Author

Reinhard Zumkeller, May 10 2006

Status

approved