8-42=-34, 76-8=68 (2×34), -60-76=-136 (-2×68), 212-(-60)=272 (2×136), -332-212=-544 (-2×272).
The pattern indicates that we should double -544=-1088 and negate: 1088. So the next term is 1088-332=756.
42, 8, 76, -60, 212, -332, 756.
Formula for nth term is 42+34((-2)ⁿ-1)/3 for n≥0.