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%I #13 Jun 28 2019 07:16:25
%S 32,245,448,3747,24495,62498,248998,2449552,6393747,6244998,244949995,
%T 498998998,2449489753,24498999998,28284271249,248997999998,
%U 498998999999,4989989999997,24899979999998
%N Smallest number k containing no zero digit such that k^2 contains exactly n zeros.
%C The corresponding squares are in A134847.
%C Browkin (see link, p. 29) gives a number without zero digits whose square has 26 zeros: 4472135954999579392819^2 = 20000000000000000000005837591200400708766761. However, he does not claim that it is the smallest such number, so a(26) <= 4472135954999579392819.
%C Indeed, there are much smaller candidates for a(26), such as 489899998999999999. We also have a(20) <= 49899989999999 and a(21) <= 498998998999998. - _Giovanni Resta_, Jun 28 2019
%H Jerzy Browkin, <a href="https://web.archive.org/web/20071220044826/http://www.impan.gov.pl/Kryptologia/GROEB1.pdf">Groebner basis</a> (in Polish)
%e a(1) = 32 because 32 is the smallest number without zero digits whose square has exactly one zero: 1024.
%Y Cf. A134843, A134844, A134845, A134847.
%K nonn,base,more
%O 1,1
%A _Artur Jasinski_, Nov 13 2007
%E Edited and a(11), a(12), a(13) added by _Klaus Brockhaus_, Nov 20 2007
%E a(14)-a(15) from _Lars Blomberg_, Jun 25 2011
%E a(16)-a(19) from _Giovanni Resta_, Jun 28 2019
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