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%I #14 Jan 02 2022 00:10:28
%S 0,1,2,10,11,12,18,20,21,32,38,48,49,100,101,102,110,111,120,149,152,
%T 179,180,182,200,201,210,318,320,321,332,338,348,351,361,362,380,451,
%U 452,462,480,482,490,548,549,649,1000,1001,1002,1010,1011,1012,1020,1021
%N Numbers k such that k^2 contains no digit greater than 4.
%H Harvey P. Dale, <a href="/A158304/b158304.txt">Table of n, a(n) for n = 1..1000</a>
%H Erich Friedman, <a href="https://erich-friedman.github.io/numbers.html">What's Special About This Number?</a>
%p A158304 := proc(n) option remember; if n= 1 then 0; else for a from procname(n-1)+1 do d := convert(convert(a^2,base,10),set) ; if max(op(d)) <= 4 then return a; end if; end do; end if; end proc:
%p seq(A158304(n),n=1..100) ; # _R. J. Mathar_, May 23 2010
%t Select[Range[0,1100],Max[IntegerDigits[#^2]]<5&] (* _Harvey P. Dale_, Nov 06 2016 *)
%Y Cf. A158082, A136810.
%K nonn,base
%O 1,3
%A _N. J. A. Sloane_, May 23 2010
%E Extended by several correspondents, May 24 2010
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