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A015898
Numbers k such that k | 9^k + 9.
11
1, 2, 3, 6, 9, 10, 18, 30, 90, 123, 730, 7086, 172426, 300243, 372390, 449674, 1812298, 5027914, 5307130, 17214354, 20788426, 84929451, 101992426, 102177370, 103544442, 106494770, 161388338, 181327546, 193710249, 207083626
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[10^5], Mod[PowerMod[9, #, #] + 9, #] == 0 &] (* Giovanni Resta, Oct 23 2018 *)
KEYWORD
nonn
EXTENSIONS
Missing a(2)-a(4) from Giovanni Resta, Oct 23 2018
STATUS
approved