Complete the recursive formula of the arithmetic sequence 12, 10, 8, 6,...12,10,8,6,...12, comma, 10, comma, 8, comma, 6, comma, point, point, point.
b(1)=b(1)=b, left parenthesis, 1, right parenthesis, equals
b(n)=b(n-1)+b(n)=b(nā1)+b, left parenthesis, n, right parenthesis, equals, b, left parenthesis, n, minus, 1, right parenthesis, plus