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%I #12 Apr 28 2019 18:05:52
%S 2,17,157,1547,15094,203879,0,0,0
%N Least n-digit number whose square is exclusionary, or 0 if no such number exists.
%C m has an exclusionary square if m consists of distinct digits and m^2 is made up only of digits not appearing in m.
%C a(10) = 0 since 10-digit numbers either use all digits or at least one digit more than once; a(n) = 0 for n > 10 since numbers with more than 10 digits use at least one digit more than once.
%D H. Ibstedt, Solution to Problem 2623 "Exclusionary Powers", Journal of Recreational Mathematics pp. 346-9 Vol. 32 no. 4 2003-4 Baywood NY.
%Y Cf. A112322 (corresponding squares), A110815.
%K nonn,base,fini
%O 1,1
%A _Lekraj Beedassy_ and _Klaus Brockhaus_, Sep 08 2005
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