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( a + 1) + ( a + 2) + ( a + 3 ) + ( a + 4 ) +......+ ( a + 10 ) = 205,( a + 1) + ( a +3) + ( a + 5 ) + ( a + 7 ) +......+ ( a + 25 ) = 234, ( a + 2) + ( a +6) + ( a + 12 ) + ( a + 20 ) +......+ ( a + 90 ) =411, ( a + 5) + ( a +10) + ( a + 15 ) + ( a + 20 ) +......+ ( a + 45 ) = 261

( a+1) + ( a+2) + ( a+ 3 ) + ( a + 4 ) +......+ ( a + 10 ) = 205
( a+1) + ( a+3) + ( a+ 5 ) + ( a + 7 ) +......+ ( a + 25 ) = 234
( a+2) + ( a+6) + ( a+ 12 ) + ( a + 20 ) +......+ ( a + 90 ) =411
( a+5) + ( a+10) + ( a+ 15 ) + ( a + 20 ) +......+ ( a + 45 ) = 261