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a(n) = smallest prime which can be expressed as a sum of distinct powers of n.
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%I #10 Sep 20 2017 19:23:20

%S 2,3,5,5,7,7,73,739,11,11,13,13,197,241,17,17,19,19,401,463,23,23,577,

%T 10171901,677,757,29,29,31,31,32801,1123,1336337,44101,37,37,1483,

%U 59359,41,41,43,43,85229,93151,47,47,110641,13847169701,2551,345157903,53,53

%N a(n) = smallest prime which can be expressed as a sum of distinct powers of n.

%C a(n) = smallest prime whose base n representation contains only zeros and 1's.

%C Values of n at which a(n) reach record values are: 2, 3, 4, 6, 8, 9, 25, 49, 91, 121, 187, 201, 301, 721, 799, 841... Notably, many of them are squares of primes. - _Ivan Neretin_, Sep 20 2017

%H Ivan Neretin, <a href="/A077724/b077724.txt">Table of n, a(n) for n = 2..10000</a>

%t Table[i = p = 1; While[! PrimeQ[p], p = FromDigits[IntegerDigits[i++, 2], n]]; p, {n, 2, 53}] (* _Ivan Neretin_, Sep 20 2017 *)

%Y Cf. A020449, A000695, A033046, A077717, A077718, A077719, A077720, A077721, A077722, A077723.

%K nonn

%O 2,1

%A _Amarnath Murthy_, Nov 19 2002

%E More terms from _Sascha Kurz_, Jan 03 2003