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Odd numbers which when cubed give number composed just of the digits 0, 1, 2, 3.
2

%I #13 Mar 14 2020 05:53:58

%S 1,11,101,1001,10001,100001,684917,1000001,10000001,100000001,

%T 1000000001,10000000001,100000000001,1000000000001,10000000000001,

%U 100000000000001,1000000000000001,10000000000000001,100000000000000001,1000000000000000001

%N Odd numbers which when cubed give number composed just of the digits 0, 1, 2, 3.

%C Note that 684917 (whose cube is 321302302131323213) so far is the only entry not of the form 10^x + 1.

%t Do[ If[ Union[ IntegerDigits[ n^3 ] ] [ [ -1 ] ] < 4, Print[ n ] ], {n, 0, 10^9} ]

%o (Python)

%o A031997_list = [n for n in range(1,10**6,2) if max(str(n**3)) <= '3'] # _Chai Wah Wu_, Feb 23 2016

%Y Cf. A030175.

%K nonn,base,more

%O 1,2

%A _Robert G. Wilson v_, Jun 23 2001

%E Term 0 removed and a(12)-a(17) added by _Chai Wah Wu_, Feb 25 2016

%E a(18)-a(20) from _Giovanni Resta_, Mar 14 2020