A084668 Brilliant Niven numbers, i.e., numbers with two prime factors of the same length (in decimal notation) which are also divisible by the sum of their digits.

4, 6, 9, 10, 21, 209, 247, 407, 481, 629, 803, 1387, 1679

Offset

1,1

Comments

Dean Hickerson proved that this sequence is finite.

Links

Table of n, a(n) for n=1..13.

Example

a(6) = 209: 209 = 11*19 and 2 + 0 + 9 = 11.

Crossrefs

Cf. A005349, A078972.

Sequence in context: A235108 A215478 A118693 * A085842 A356135 A131220

Adjacent sequences: A084665 A084666 A084667 * A084669 A084670 A084671

Keyword

base,easy,fini,full,nonn

Author

Jason Earls, Jun 29 2003

Status

approved