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Squares that remain squares when prefixed with a 3.
3

%I #12 Mar 15 2024 02:24:06

%S 4225,30625,330625,422500,3062500,4515625,33062500,42250000,306250000,

%T 451562500,953265625,3306250000,4225000000,30625000000,39451890625,

%U 45156250000,95326562500,282891015625,330625000000,422500000000,3062500000000,3560297265625

%N Squares that remain squares when prefixed with a 3.

%H Chai Wah Wu, <a href="/A167037/b167037.txt">Table of n, a(n) for n = 1..1000</a>

%e 4225 = 65^2 is a square and becomes the square 34225 = 185^2 if a 3 is attached in front.

%K nonn,base

%O 1,1

%A _Claudio Meller_, Oct 27 2009

%E Keyword:base added by _R. J. Mathar_, Oct 28 2009

%E More terms from _Chai Wah Wu_, Sep 11 2014