A058444 - OEIS

%I #16 Oct 18 2024 14:36:05

%S 4,9,49,9409,44944,994009,9909904,99940009,404090404,9999400009,

%T 999994000009,4004009004004,9449494444009,99999940000009,

%U 9999999400000009,40004000900040004,999999994000000009,99999999940000000009,400004000090000400004,9999999999400000000009

%N Squares composed of digits {0,4,9}, not ending with zero.

%C Includes all numbers of the form (10^k - 3)^2 for k >= 1 and of the form (2*100^k + 10^k + 2)^2 for k >= 1. - _Andrew Howroyd_, Oct 18 2024

%H Zhao Hui Du, <a href="/A058444/b058444.txt">Table of n, a(n) for n = 1..54</a>

%H Patrick De Geest, <a href="http://www.worldofnumbers.com/threedigits.htm">Index to related sequences</a>

%H Hisanori Mishima, <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#049">Sporadic tridigital solutions</a>

%F a(n) = A058443(n)^2. - _Andrew Howroyd_, Oct 18 2024

%Y Cf. A058443.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Nov 15 2000