Concatenation : A^2 || B^2 = C^2, (A=4,5,6,7,8.9)

$A^2 \; || \; B^2 \; = \; C^2$,   with   $A \; = \; 4, \; 5, \; 6, \; 7, \; 8, \; 9$

$A \; = \; 4$

$4^2 \; || \; B^2 \; = \; C^2$

$41^2 \; = \; 1681 \; = \; 16 || 81 \; = \; 4^2 || 9^2$

$130^2 \; = \; 16900 \; = \; 16 || 900 \; = \; 4^2 || 30^2$

$410^2 \; = \; 168100 \; = \; 16 || 8100 \; = \; 4^2 || 90^2$

$1300^2 \; = \; 1690000 \; = \; 16 || 90000 \; = \; 4^2 || 300^2$

$4100^2 \; = \; 16810000 \; = \; 16 || 810000 \; = \; 4^2 || 900^2$

$13000^2 \; = \; 169000000 \; = \; 16 || 9000000 \; = \; 4^2 || 3000^2$

$41000^2 \; = \; 1681000000 \; = \; 16 || 81000000 \; = \; 4^2 || 9000^2$

$41225^2 \; = \; 1699500625 \; = \; 16 || 99500625 \; = \; 4^2 || 9975^2$

$129325^2 \; = \; 16724955625 \; = \; 16 || 724955625 \; = \; 4^2 || 26925^2$

$130000^2 \; = \; 16900000000 \; = \; 16 || 900000000 \; = \; 4^2 || 30000^2$

$410000^2 \; = \; 168100000000 \; = \; 16 || 8100000000 \; = \; 4^2 || 90000^2$

$412250^2 \; = \; 169950062500 \; = \; 16 || 9950062500 \; = \; 4^2 || 99750^2$

$A \; = \; 5$

$5^2 \; || \; B^2 \; = \; C^2$

Jeff Curtis found:

$160903431640625^2$
$= 25889914313729282379150390625$
$= 25 \; || \; 889914313729282379150390625$
$= 5^2 \; || \; 29831431640625^2$

$A \; = \; 6$

$6^2 \; || \; B^2 \; = \; C^2$

$190^2 \; = \; 36100 \; = \; 36 \; || \; 100 \; = \; 6^2 \; || \; 10^2$

$1900^2 \; = \; 3610000 \; = \; 36 \; || \; 10000 \; = \; 6^2 \; || \; 100^2$

$A \; = \; 7$

$7^2 \; || \; B^2 \; = \; C^2$

$223^2 \; = \; 49729 \; = \; 49 \; || \; 729 \; = \; 7^2 \; || \; 27^2$

$2225^2 \; = \; 4950625 \; = \; 49 \; || \; 50625 \; = \; 7^2 \; || \; 225^2$

$2230^2 \; = \; 4972900 \; = \; 49 \; || \; 72900 \; = \; 7^2 \; || \; 270^2$

$A \; = \; 8$

$8^2 \; || \; B^2 \; = \; C^2$

Jeff Curtis found:

$8009001265625^2 \; = \; 64144101272782851806640625$

$64 \; || \; 144101272782851806640625 \; = \; 8^2 \; || \; 379606734375^2$

$A \; = \; 9$

$9^2 \; || \; B^2 \; = \; C^2$

$285^2 \; = \; 81225 \; = \; 81 \; || \; 225 \; = \; 9^2 \; || \; 15^2$

$905^2 \; = \; 819025 \; = \; 81 \; || \; 9025 \; = \; 9^2 \; || \; 95^2$

$2850^2 \; = \; 8122500 \; = \; 81 \; || \; 22500 \; = \; 9^2 \; || \; 150^2$

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