345
( c 2 + d 2 ) = ( c 2 ) + ( d 2 )
451
( a 2 + b 2 + c 2 + d 2 ) = ( a 2 + b 2 + c 2 ) + ( d 2 )
513
( a 2 + b 2 + c 2 + d 2 ) = ( a 2 + b 2 ) + ( c 2 + d 2 )
134
( a 2 + b 2 + c 2 ) = ( a 2 + b 2 ) + ( c 2 )