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Single Curio View: (Seek other curios for this number) The 121st prime is 661. If we concatenate 121 and 661, or 661 and 121, we get two more primes (121661 and 661121). This is the smallest case of what high school algebra teacher Terry Trotter (19412004) called OPPO primes (O = Ordinal position, and P = Prime).
Submitted: 20010729 18:58:23; Last Modified: 20080731 20:25:44.
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