ceta_eq: termination proof not accepted 1: error below switch to dependency pairs 1.1: error below the dependency graph processor 1.1.2: error below the reduction pair processor 1.1.2.1: error below the reduction pair processor 1.1.2.1.1: error below the reduction pair processor 1.1.2.1.1.1: error when applying the reduction pair processor with usable rules to remove from the DP problem pairs: active#(recip(X)) -> active#(X) active#(s(X)) -> active#(X) active#(dbl(X)) -> active#(X) rules: active(terms(N)) -> mark(cons(recip(sqr(N)), terms(s(N)))) active(sqr(0)) -> mark(0) active(sqr(s(X))) -> mark(s(add(sqr(X), dbl(X)))) active(dbl(0)) -> mark(0) active(dbl(s(X))) -> mark(s(s(dbl(X)))) active(add(0, X)) -> mark(X) active(add(s(X), Y)) -> mark(s(add(X, Y))) active(first(0, X)) -> mark(nil) active(first(s(X), cons(Y, Z))) -> mark(cons(Y, first(X, Z))) active(terms(X)) -> terms(active(X)) active(cons(X1, X2)) -> cons(active(X1), X2) active(recip(X)) -> recip(active(X)) active(sqr(X)) -> sqr(active(X)) active(s(X)) -> s(active(X)) active(add(X1, X2)) -> add(active(X1), X2) active(add(X1, X2)) -> add(X1, active(X2)) active(dbl(X)) -> dbl(active(X)) active(first(X1, X2)) -> first(active(X1), X2) active(first(X1, X2)) -> first(X1, active(X2)) add(mark(X1), X2) -> mark(add(X1, X2)) add(X1, mark(X2)) -> mark(add(X1, X2)) add(ok(X1), ok(X2)) -> ok(add(X1, X2)) cons(mark(X1), X2) -> mark(cons(X1, X2)) cons(ok(X1), ok(X2)) -> ok(cons(X1, X2)) dbl(mark(X)) -> mark(dbl(X)) dbl(ok(X)) -> ok(dbl(X)) first(mark(X1), X2) -> mark(first(X1, X2)) first(X1, mark(X2)) -> mark(first(X1, X2)) first(ok(X1), ok(X2)) -> ok(first(X1, X2)) proper(terms(X)) -> terms(proper(X)) proper(cons(X1, X2)) -> cons(proper(X1), proper(X2)) proper(recip(X)) -> recip(proper(X)) proper(sqr(X)) -> sqr(proper(X)) proper(s(X)) -> s(proper(X)) proper(0) -> ok(0) proper(add(X1, X2)) -> add(proper(X1), proper(X2)) proper(dbl(X)) -> dbl(proper(X)) proper(first(X1, X2)) -> first(proper(X1), proper(X2)) proper(nil) -> ok(nil) recip(mark(X)) -> mark(recip(X)) recip(ok(X)) -> ok(recip(X)) s(mark(X)) -> mark(s(X)) s(ok(X)) -> ok(s(X)) sqr(mark(X)) -> mark(sqr(X)) sqr(ok(X)) -> ok(sqr(X)) terms(mark(X)) -> mark(terms(X)) terms(ok(X)) -> ok(terms(X)) top(mark(X)) -> top(proper(X)) top(ok(X)) -> top(active(X)) the pairs active#(s(X)) -> active#(X) could not apply the generic root reduction pair processor with the following SCNP-version with mu = MS and the level mapping defined by pi(active#) = [(epsilon,0),(1,0)] Argument Filter: pi(active#/1) = [] pi(recip/1) = 1 pi(s/1) = [1] pi(dbl/1) = 1 RPO with the following precedence precedence(active#[1]) = 0 precedence(s[1]) = 1 precedence(_) = 0 and the following status status(active#[1]) = lex status(s[1]) = lex status(_) = lex problem when orienting DPs cannot orient pair active#(recip(X)) -> active#(X) weakly: [(active#(recip(X)),0),(recip(X),0)] >=mu [(active#(X),0),(X,0)] could not be ensured