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Primes p equal to the sum in base 3 of the digits of all primes <= p.
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%I #14 May 12 2014 11:49:46

%S 3,37,695663,695881,1308731,1308757,1313153,1314301,1326097,1766227,

%T 3204779,14328191

%N Primes p equal to the sum in base 3 of the digits of all primes <= p.

%F prime(n) such that, using base 3, prime(n) = sum_{1..n} A239619(i).

%e 3 = digit-sum(primes <= 3,base=3) = sum(2) + sum(1,0). 37 = digit-sum(primes <= 37,base=3) = sum(2) + sum(1,0) + sum(1,2) + sum(2,1) + sum(1,0,2) + sum(1,1,1) + sum(1,2,2) + sum(2,0,1) + sum(2,1,2) + sum(1,0,0,2) + sum(1,0,1,1) + sum(1,1,0,1).

%o (PARI) sdt(n) = my(d = digits(n, 3)); sum(i=1, #d, d[i]);

%o lista(nn) = {sp = 0; forprime(p=1, nn, sp += sdt(p); if (p == sp, print1(p, ", ")););} \\ _Michel Marcus_, May 02 2014

%Y Cf. A168161 (similar in base 2), A240886 (similar but excluding p from the sum).

%K nonn,more,base

%O 1,1

%A _Anthony Sand_, May 01 2014