A333133 7-Kaprekar numbers.

1, 627615, 4444444, 4927941, 5072059, 5555556, 9372385, 9999999

Offset

1,2

Comments

No n-Kaprekar number k can have more than n digits because then the number to the left of the plus sign would have more digits than k itself, meaning the sum will always be greater than k.

Links

Table of n, a(n) for n=1..8.

Example

627615 is in this sequence because inserting a + before the 7th digit from the right of 627615^2 = 393900588225 yields 39390 + 0588225, which equals 627615 (the starting number).

Crossrefs

Cf. A006886, A037042, A053394, A053395, A053396, A053397.

Sequence in context: A053877 A236008 A141815 * A172701 A119398 A252894

Adjacent sequences: A333130 A333131 A333132 * A333134 A333135 A333136

Keyword

nonn,fini,full,base

Author

Eric Fox, Mar 09 2020

Status

approved