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A167045 Squares that remains a square when some single digit is inserted in front of its decimal expansion.

%I A167045 #12 Jul 19 2016 16:54:58
%S A167045 1,4,9,25,100,225,400,625,900,1225,2025,2500,3025,4225,5625,7225,
%T A167045 10000,22500,30625,40000,50625,62500,70225,75625,90000,93025,122500,
%U A167045 202500,250000,302500,330625,422500,455625,562500,722500,765625,950625,1000000
%N A167045 Squares that remains a square when some single digit is inserted in front of its decimal expansion.
%H A167045 Chai Wah Wu, <a href="/A167045/b167045.txt">Table of n, a(n) for n = 1..1000</a>
%F A167045 Union of A167035, A167036, A167037, A167038, A167039, A167041, A167042, A167043 and A167044. [_R. J. Mathar_, Oct 30 2009]
%e A167045 225 is in the sequence because both 225 and 1225 are squares.
%p A167045 a := proc (n) local s, c, j: s := proc (n) options operator, arrow: nops(convert(n, base, 10)) end proc: c := 0: for j to 9 do if type(sqrt(j*10^s(n^2)+n^2), integer) = true then c := c+1 else end if end do: if 0 < c then n^2 else end if end proc: seq(a(n), n = 1 .. 1200); # _Emeric Deutsch_, Nov 01 2009
%t A167045 srsQ[n_]:=AnyTrue[Range[9]*10^IntegerLength[n]+n,IntegerQ[Sqrt[#]]&]; Select[ Range[1200]^2,srsQ] (* The program uses the AnyTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jul 19 2016 *)
%K A167045 nonn,base
%O A167045 1,2
%A A167045 _Claudio Meller_, Oct 27 2009
%E A167045 Edited by _N. J. A. Sloane_, Oct 29 2009
%E A167045 More terms from _R. J. Mathar_ and _Emeric Deutsch_, Oct 30 2009