A085070 a(1) = 1; then the smallest number a(n) == -1 mod a(n-1) such that tau(a(n)) = n.

1, 2, 9, 26

Offset

1,2

Comments

a(5) doesn't exist because -1 is not a 4th power mod 26. - David Wasserman, Jan 12 2005

Links

Table of n, a(n) for n=1..4.

Example

a(3) = 9, a(4) = 26 == -1 (mod 9) and tau(26)= 4.

Crossrefs

Cf. A085069.

Sequence in context: A101051 A356401 A218460 * A083383 A221574 A082289

Adjacent sequences: A085067 A085068 A085069 * A085071 A085072 A085073

Keyword

fini,full,nonn

Author

Amarnath Murthy, Jun 30 2003

Status

approved