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A135464 Numbers n with property that for each single digit d of the base 3 expansion of n, we can also see the base 3 expansion of d^2 as a substring. Also n may not contain any 0 digits.

%I A135464 #11 Aug 20 2023 10:51:49
%S A135464 1,11,111,112,211,1111,1112,1121,1122,1211,2111,2112,2211,11111,11112,
%T A135464 11121,11122,11211,11212,11221,11222,12111,12112,12211,21111,21112,
%U A135464 21121,21122,21211,22111,22112,22211,111111,111112,111121
%N A135464 Numbers n with property that for each single digit d of the base 3 expansion of n, we can also see the base 3 expansion of d^2 as a substring. Also n may not contain any 0 digits.
%C A135464 The base 3 expansion of n may only contain 1's and 2's and if a 2 is present then 11 must also be present. These are the only restrictions.
%H A135464 David Applegate, <a href="/A135464/b135464.txt">Table of n, a(n) for n = 1..300</a>
%o A135464 (AWK) awk 'function g(s,v,n){if (n==0){if (index(s,"2")==0||index(s,"11")>0)print v;}else{g(s "1",v*3+1,n-1); g(s "2",v*3+2,n-1);}}BEGIN{for (i=1; i<=8; i++)g("",0,i);}' # _David Applegate_
%o A135464 (C++) // See the Applegate link in A135463.
%Y A135464 Base-3 analog of A134962. Cf. A135465.
%K A135464 nonn,base,easy
%O A135464 1,2
%A A135464 _David Applegate_ and _N. J. A. Sloane_, Feb 07 2008