A339673 Numbers that cannot be expressed as sum of at most nine repdigits numbers. One may not add two integers with the same repeated digit.

25427, 31427, 32027, 32087, 32093, 37032, 37583, 37643, 37693, 49390, 49501, 50611, 60490, 60501, 60611, 61600, 61601, 61611, 61711, 61721, 61722, 62958, 62959, 62969, 63069, 64069, 65427, 72958, 72959, 72969, 73069, 73958, 73959, 73969, 74058, 74059, 74068

Offset

1,1

Comments

Computer solutions found by Oscar Volpatti.

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Carlos Rivera and Rodolfo Kurchan, Puzzle 1027. Integers as sum of distinct repdigits, The prime puzzles & problems connection.

Example

8888 and 888 cannot be used in the same expression.
Examples: 25599 = 22222 + 3333 + 44, 98765 = 88888 + 7777 + 1111 + 555 + 333 + 99 + 2.
It appears that 987654 and 987650 cannot be expressed in this way.
25427 is the smallest number without solution.
Smallest solution that ends with digits from 0 to 9 (solutions from Oscar Volpatti): 0: 49390 1: 49501 2: 37032 3: 32093 4: 143204 5: 254315 6: 74106 7: 25427 8: 62958 9: 62959.

Crossrefs

Cf. A235400.

Sequence in context: A203090 A251227 A183648 * A324635 A242141 A124997

Adjacent sequences: A339670 A339671 A339672 * A339674 A339675 A339676

Keyword

base,nonn

Author

Rodolfo Kurchan, Jan 17 2021

Status

approved