repunit(n, base) := (base^n-1)/(base-1)$
repunit_primes(base) := sublist_indices(makelist(repunit(i, base), i, 1, 1000), primep)$

for i from 2 thru 16 do(
    sprint("Base", i),
    newline(),
    rup: repunit_primes(i),
    if length(rup) > 0 then apply(sprint, rup) else sprint("None"),
    newline()
)$