A094098 Number of divisor chains of length n in which the first term is a divisor of n(n+1)/2 ("cyclic" divisor chains).

1, 0, 2, 0, 2, 0, 3, 0, 5, 0, 6, 0, 6, 0, 147, 1, 22, 2, 27, 165, 519, 0, 516, 2021, 1912, 506, 45658, 514, 7308, 1535, 30746, 68918, 145920, 1370

Offset

1,3

Comments

A divisor chain of length n is an arrangement of 1..n such that each term is a divisor of the sum of the preceding terms.

Links

Table of n, a(n) for n=1..34.

Crossrefs

Cf. A067957, A094097, A094099.

Sequence in context: A005868 A035455 A029191 * A326844 A261079 A182485

Adjacent sequences: A094095 A094096 A094097 * A094099 A094100 A094101

Keyword

nonn,more

Author

Christopher Landauer, May 04 2004

Extensions

a(29)-a(34) from John W. Layman, May 07 2004

Status

approved