234
( b 2 + c 2 ) = ( b 2 ) + ( c 2 )
345
( c 2 + d 2 ) = ( c 2 ) + ( d 2 )
452
( b 2 + c 2 + d 2 ) = ( b 2 + c 2 ) + ( d 2 )
523
( b 2 + c 2 + d 2 ) = ( b 2 ) + ( c 2 + d 2 )