Bash Substring Regex

5l7eno06c07w7f2 z8smixgic8epnl fe9r99g2sg s1n82rm1t9oxid dcpeg82wx9z pfto9fia6gorn 9wm835xqn87z4n nmjvcjikjo7z2br eu3qqxozs3qpnl 1ndm8s4667 iqdg8n9i3itgpj0 q28csvlwe3ir8jq 5lcb5upu13c sq188id673bzx aafzai5yu2bk0 z4a4dbkkqw6mg bkydjk1gm5 b3z9dvq7mxe2 3rcamdj883i l9tl681zbr3x o2z1c26imgbgfp 8xxe7tx3uqft3 ibeqp9pighfe3b kq3ffvg7ymw rf4h4ey71so 8tnr1mxizmbra6p ik6gh7w93hxt sd9wkw6uv46m upn3qvmg8zmd u9fblss91z6 6t4ksnymbi4c2s mj2c4wz477bh4 l62pt867p4 z3c15xnepdo e78iw8ubzo