a(n) is the smallest odd prime p such that 2^n*p has n digits but has at most two distinct digits; or 0 if no such prime exists.

A124244

a(n) is the smallest odd prime p such that 2^n*p has n digits but has at most two distinct digits; or 0 if no such prime exists.

Terms

    a(0) =3a(1) =3a(2) =29a(3) =101a(4) =691a(5) =15467a(6) =39023a(7) =71023a(8) =437977a(9) =4344227a(10) =21158903a(11) =109739989a(12) =344590189a(13) =2956838897a(14) =6781690193a(15) =0a(16) =85533990571a(18) =0a(20) =0a(21) =0a(23) =0

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