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- #!/usr/bin/ruby
- # Numbers k such that A061015(k) is prime.
- # https://oeis.org/A092062
- # Known terms:
- # 2, 10, 18, 36, 90, 759
- # a(7) > 1850. - Michael S. Branicky, Jun 27 2022
- var lower_bound = 2144
- var sum = 0
- for k in (1..1e6) {
- sum += 1/(prime(k)**2)
- say ":: Testing: #{k} (len: #{sum.nu.len})"
- if (k>=lower_bound && sum.nu.is_prob_prime) {
- die "Found: #{k}"
- }
- }
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