A089318 Smallest prime of the form an n-th power followed by digit 1.
31, 41, 271, 811, 77761, 641, 21871, 16796161, 196831, 259374246011, 19773267431, 40961, 9688901040700000000000001, 163841, 1368800680154120519681, 1214395310965942517761, 58744031063604200188795536431, 3874204891, 2748779069441, 1757494343868923397049845066579063588307980412147890120011
Offset: 1
Examples
a(4) = 811 is the prime which is the concatenation of 3^4 and 1. 161 is not a prime.
Crossrefs
Cf. A089319.
Programs
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PARI
a(n) = my(k=2); while (!isprime(10*k^n+1), k++); 10*k^n+1; \\ Michel Marcus, Mar 08 2025
Extensions
More terms from David Wasserman, Sep 09 2005
Missing a(1) inserted and more terms from Michel Marcus, Mar 08 2025