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A333133
7-Kaprekar numbers.
4
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.
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
KEYWORD
nonn,fini,full,base
AUTHOR
Eric Fox, Mar 09 2020
STATUS
approved