/usr/share/acl2-6.3/books/centaur/misc/ is in acl2-books-certs 6.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-6.3/books/centaur/misc/1d-arr.cert
/usr/share/acl2-6.3/books/centaur/misc/2d-arr.cert
/usr/share/acl2-6.3/books/centaur/misc/absstobjs.cert
/usr/share/acl2-6.3/books/centaur/misc/alist-defs.cert
/usr/share/acl2-6.3/books/centaur/misc/alist-equiv.cert
/usr/share/acl2-6.3/books/centaur/misc/alist-witness.cert
/usr/share/acl2-6.3/books/centaur/misc/ap.cert
/usr/share/acl2-6.3/books/centaur/misc/arith-equiv-defs.cert
/usr/share/acl2-6.3/books/centaur/misc/arith-equivs.cert
/usr/share/acl2-6.3/books/centaur/misc/arrays.cert
/usr/share/acl2-6.3/books/centaur/misc/beta-reduce-full.cert
/usr/share/acl2-6.3/books/centaur/misc/bitarr.cert
/usr/share/acl2-6.3/books/centaur/misc/context-rw.cert
/usr/share/acl2-6.3/books/centaur/misc/count-up.cert
/usr/share/acl2-6.3/books/centaur/misc/defapply.cert
/usr/share/acl2-6.3/books/centaur/misc/dfs-measure.cert
/usr/share/acl2-6.3/books/centaur/misc/equal-by-nths.cert
/usr/share/acl2-6.3/books/centaur/misc/equal-sets.cert
/usr/share/acl2-6.3/books/centaur/misc/evaluator-metatheorems.cert
/usr/share/acl2-6.3/books/centaur/misc/fal-graphs.cert
/usr/share/acl2-6.3/books/centaur/misc/fast-alists.cert
/usr/share/acl2-6.3/books/centaur/misc/fast-cons-memo.cert
/usr/share/acl2-6.3/books/centaur/misc/filter-alist.cert
/usr/share/acl2-6.3/books/centaur/misc/hons-alphorder-merge.cert
/usr/share/acl2-6.3/books/centaur/misc/hons-extra.cert
/usr/share/acl2-6.3/books/centaur/misc/hons-remove-dups.cert
/usr/share/acl2-6.3/books/centaur/misc/hons-sets.cert
/usr/share/acl2-6.3/books/centaur/misc/intern-debugging.cert
/usr/share/acl2-6.3/books/centaur/misc/interp-function-lookup.cert
/usr/share/acl2-6.3/books/centaur/misc/introduce-var.cert
/usr/share/acl2-6.3/books/centaur/misc/iter.cert
/usr/share/acl2-6.3/books/centaur/misc/lists.cert
/usr/share/acl2-6.3/books/centaur/misc/load-stobj-tests.cert
/usr/share/acl2-6.3/books/centaur/misc/load-stobj.cert
/usr/share/acl2-6.3/books/centaur/misc/memory-mgmt-logic.cert
/usr/share/acl2-6.3/books/centaur/misc/memory-mgmt.cert
/usr/share/acl2-6.3/books/centaur/misc/nat-list-duplicates.cert
/usr/share/acl2-6.3/books/centaur/misc/natarr.cert
/usr/share/acl2-6.3/books/centaur/misc/nats-equiv.cert
/usr/share/acl2-6.3/books/centaur/misc/nth-equiv.cert
/usr/share/acl2-6.3/books/centaur/misc/numlist.cert
/usr/share/acl2-6.3/books/centaur/misc/osets-witnessing.cert
/usr/share/acl2-6.3/books/centaur/misc/patterns.cert
/usr/share/acl2-6.3/books/centaur/misc/remove-assoc.cert
/usr/share/acl2-6.3/books/centaur/misc/resize-list.cert
/usr/share/acl2-6.3/books/centaur/misc/rewrite-rule.cert
/usr/share/acl2-6.3/books/centaur/misc/seed-random.cert
/usr/share/acl2-6.3/books/centaur/misc/smm-impl.cert
/usr/share/acl2-6.3/books/centaur/misc/smm.cert
/usr/share/acl2-6.3/books/centaur/misc/sneaky-load.cert
/usr/share/acl2-6.3/books/centaur/misc/sparsemap-impl.cert
/usr/share/acl2-6.3/books/centaur/misc/sparsemap.cert
/usr/share/acl2-6.3/books/centaur/misc/stobj-swap.cert
/usr/share/acl2-6.3/books/centaur/misc/suffixp.cert
/usr/share/acl2-6.3/books/centaur/misc/tailrec.cert
/usr/share/acl2-6.3/books/centaur/misc/top.cert
/usr/share/acl2-6.3/books/centaur/misc/tshell-tests.cert
/usr/share/acl2-6.3/books/centaur/misc/tshell.cert
/usr/share/acl2-6.3/books/centaur/misc/tuplep.cert
/usr/share/acl2-6.3/books/centaur/misc/u32-listp.cert
/usr/share/acl2-6.3/books/centaur/misc/universal-equiv.cert
/usr/share/acl2-6.3/books/centaur/misc/vecs-ints.cert
/usr/share/acl2-6.3/books/centaur/misc/witness-cp.cert