0
Output a unique sign sequence
A sign sequence is an infinite sequence consisting entirely of \$1\$ and \$-1\$. These can be constructed a number of ways, for example:
Alternating signs: \$1, -1, 1, -1, ...\$
\$-1\$ for primes, \$1\$ for non-primes: \$1, -1, -1, 1, -1, 1, -1, ...\$
All \$1\$s: \$...