A380568 Choose two different numbers x and y from 2 to 9. a(n) is the number that consists solely of the digits x or y and is the smallest number divisible by both of them.

24, 36, 288, 448, 2232, 2772, 3444, 3555, 3888, 4464, 5775, 6696, 8688, 33399, 37737, 44744, 76776, 7888888, 2222222292, 4444444944, 5555555595, 8888889888, 77777779779

Offset

1,1

Links

Table of n, a(n) for n=1..23.

Carlos Rivera, Puzzle 306. Generalized LYM Puzzle, The Prime Puzzles and Problems Connection.

Example

  x | y |
----+---+---------------------------------
  2 | 3 |        2232 = 2 * 3 * 372.
  2 | 4 |          24 = 2 * 4 * 3.
  2 | 5 |
  2 | 6 |
  2 | 7 |        2772 = 2 * 7 * 198.
  2 | 8 |         288 = 2 * 8 * 18.
  2 | 9 |  2222222292 = 2 * 9 * 123456794.
  3 | 4 |        3444 = 3 * 4 * 287.
  3 | 5 |        3555 = 3 * 5 * 237.
  3 | 6 |          36 = 3 * 6 * 2.
  3 | 7 |       37737 = 3 * 7 * 1797.
  3 | 8 |        3888 = 3 * 8 * 162.
  3 | 9 |       33399 = 3 * 9 * 1237.
  4 | 5 |
  4 | 6 |        4464 = 4 * 6 * 186.
  4 | 7 |       44744 = 4 * 7 * 1598.
  4 | 8 |         448 = 4 * 8 * 14.
  4 | 9 |  4444444944 = 4 * 9 * 123456804.
  5 | 6 |
  5 | 7 |        5775 = 5 * 7 * 165.
  5 | 8 |
  5 | 9 |  5555555595 = 5 * 9 * 123456791.
  6 | 7 |       76776 = 6 * 7 * 1828.
  6 | 8 |        8688 = 6 * 8 * 181.
  6 | 9 |        6696 = 6 * 9 * 124.
  7 | 8 |     7888888 = 7 * 8 * 140873.
  7 | 9 | 77777779779 = 7 * 9 * 1234567933.
  8 | 9 |  8888889888 = 8 * 9 * 123456804.

Crossrefs

Sequence in context: A304616 A172424 A241286 * A334803 A070740 A175460

Adjacent sequences: A380565 A380566 A380567 * A380569 A380570 A380572

Keyword

nonn,full,fini,base

Author

Seiichi Manyama, Jan 26 2025

Status

approved