/usr/share/acl2-7.1/books/projects/symbolic/ is in acl2-books 7.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-7.1/books/projects/symbolic/generic/
/usr/share/acl2-7.1/books/projects/symbolic/generic/assertions.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/defsimulate.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/factorial-jvm-correct.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/measures.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/partial-correctness.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/tiny-fib-correct.o
/usr/share/acl2-7.1/books/projects/symbolic/generic/total-correctness.o
/usr/share/acl2-7.1/books/projects/symbolic/m5/
/usr/share/acl2-7.1/books/projects/symbolic/m5/demo.o
/usr/share/acl2-7.1/books/projects/symbolic/m5/utilities.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-fib/
/usr/share/acl2-7.1/books/projects/symbolic/tiny-fib/defstobj+.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-fib/fib-def.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-fib/tiny-rewrites.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-fib/tiny.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-triangle/
/usr/share/acl2-7.1/books/projects/symbolic/tiny-triangle/tiny-triangle-correct.o
/usr/share/acl2-7.1/books/projects/symbolic/tiny-triangle/triangle-def.o