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%I #36 Jun 01 2024 21:42:22
%S 1,0,0,0,0,0,0,99999992,998117649,0,25937424601,999999999924,0,0,0,
%T 9999999999999872,0,999999999999999252,0,99999999999999999440,0,0,0,
%U 999999999999999999999456,9999450940359923567250625,0,999999999997420003910299449,9999999999999999999999972416,0,0,0
%N a(n) = the largest multiple of n with n digits and exactly n divisors; a(n) = 0 if no such number exists.
%C Conjecture: a(n) > 0 for all nonsquarefree n except for n = 4. - _Jon E. Schoenfield_, Jun 01 2024
%F A000005(a(n)) = n if a(n) > 0.
%F a(n) >= A182749(n).
%Y Cf. A000005, A073904, A182749.
%K nonn,base
%O 1,8
%A _Jaroslav Krizek_, Nov 27 2010
%E More terms from _Harvey P. Dale_, Mar 02 2018
%E a(24)-a(25) and a(27) from _Michael S. Branicky_, May 26 2024
%E a(26), a(28) added, and a(16), a(18), a(20) corrected by _Jon E. Schoenfield_, May 26 2024
%E a(29)-a(31) from _David A. Corneth_, May 27 2024