A082236 a(1) = 1 and then numbers such that the product of n terms starting with the n-th term is an n-th power. The smallest numbers not occurring earlier are used first.

1, 2, 8, 3, 9, 4, 12, 5, 11250, 6, 45, 7, 14117880, 10, 252, 11, 225076825050, 13, 275584427455837500, 14, 12870, 15, 90090, 16, 107627520, 17, 8398288545799276315404813600, 18, 8139178347300, 19, 11718177145952331518789204880, 20, 32008977, 21

Offset

1,2

Links

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

Sean A. Irvine, Java program (github)

Example

as a(3) = 8 choose a(4) = 3 ( smallest number not occurring earlier) and a(5) = 9 to satisfy the requirement. The product of three terms starting with a(3) is 8*3*9 = 216 = 6^3.

Crossrefs

Cf. A082237.

Sequence in context: A076696 A391666 A011057 * A337822 A362269 A394507

Adjacent sequences: A082233 A082234 A082235 * A082237 A082238 A082239

Keyword

nonn

Author

Amarnath Murthy, Apr 10 2003

Extensions

Corrected and extended by David Wasserman, Aug 26 2004

a(9) onward corrected by Sean A. Irvine, Dec 01 2025

Status

approved