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%I #23 Apr 29 2022 21:27:04
%S 2,3,5,7,9,11,13,17,19,23,27,31,47,59,67,71,83,113,127,139,163,197,
%T 211,229,251,263,311,317,347,421,457,461
%N Length of repunits of which the prime factor-digit-excess computed by A095414 equals 0.
%C 541, 701, 857 are also terms. Conjecture: Except for the number 4, A046413 is a subsequence. Conjecture: except for the prime powers 9 and 27, all terms are prime. - _Chai Wah Wu_, Nov 03 2019
%C Sequence continues as 467?, 479?, 509?, 541, 557?, 571?, 577?, 593?, 599?, 617?, 643?, 647?, 661?, 673?, 683?, 691?, 701, 727?, 743?, 751?, 757?, 769?, 773?, 821?, 857, 863?, 887?, 911?, 967?, 971?, 977?, 991?, where ? marks uncertain/candidate terms. - _Max Alekseyev_, Apr 29 2022
%F Solutions to A095414(x) = 0.
%t d[1] = -1; d[n_] := Total[ IntegerLength /@ First /@ FactorInteger[(10^n - 1)/9]] - n; Select[ Range[67], d[#] == 0 &] (* _Giovanni Resta_, Jul 16 2018 *)
%Y A004023 is a subsequence.
%Y Cf. A002275, A004023, A095370, A095407, A095413-A095418.
%K nonn,more,base
%O 1,1
%A _Labos Elemer_, Jun 22 2004
%E Data corrected and extended by _Giovanni Resta_, Jul 16 2018
%E a(29)-a(32) confirmed by _Max Alekseyev_, Apr 29 2022
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