Using least parameters, we expand the step-transition operator of any linear multi-step method (LMSM) up to O(τ^s+5) with order s = 1 and rewrite the expansion of the steptransition operator for s = 2 (obtained...Using least parameters, we expand the step-transition operator of any linear multi-step method (LMSM) up to O(τ^s+5) with order s = 1 and rewrite the expansion of the steptransition operator for s = 2 (obtained by the second author in a former paper). We prove that in the conjugate relation G3^λτ o G1^τ =G2^τ o G3^λτ with G1 being an LMSM,(1) theorder of G2 can not be higher than that of G1; (2) if G3 is also an LMSM and G2 is a symplectic B-series, then the orders of G1, G2 and G3 must be 2, 2 and 1 respectively.展开更多
基金This research is supported by the Informatization Construction of Knowledge Innovation Projects of the Chinese Academy of Sciences "Supercomputing Environment Construction and Application" (INF105-SCE), and by a grant (No. 10471145) from National Natural Science Foundation of China.
文摘Using least parameters, we expand the step-transition operator of any linear multi-step method (LMSM) up to O(τ^s+5) with order s = 1 and rewrite the expansion of the steptransition operator for s = 2 (obtained by the second author in a former paper). We prove that in the conjugate relation G3^λτ o G1^τ =G2^τ o G3^λτ with G1 being an LMSM,(1) theorder of G2 can not be higher than that of G1; (2) if G3 is also an LMSM and G2 is a symplectic B-series, then the orders of G1, G2 and G3 must be 2, 2 and 1 respectively.