cp's OEIS Frontend

A241897 Primes p equal to the sum in base 3 of the digits of all primes < p - digit-sum of the index of prime p(i-1).

%I A241897 #11 Mar 02 2018 02:14:14
%S A241897 67,71,97,101,149,223,656267,697511,697951,698447,699493,700277,
%T A241897 715373,883963,888203,888211,992021,992183,992891,993241,994181,
%U A241897 1155607,1155829,1308121,1308649,1310093,1313083,1317409,1320061,1320157,1320379,1322521,1322591
%N A241897 Primes p equal to the sum in base 3 of the digits of all primes < p - digit-sum of the index of prime p(i-1).
%C A241897 There are no further solutions beyond a(46)=4539541 up to at least 10^10. - _Andrew Howroyd_, Mar 02 2018
%H A241897 Anthony Sand, <a href="/A241897/b241897.txt">Table of n, a(n) for n = 1..46</a>
%F A241897 prime(n) such that, using base 3, prime(n) = sum_{1..n-1} A239619(i) - sum_{index(n-1)}
%e A241897 67 = digit-sum(2..61,b=3) - digit-sum(index(61),b=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) + sum(1,1,1,2) + sum(1,1,2,1) + sum(1,2,0,2) + sum(1,2,2,2) + sum(2,0,1,2) + sum(2,0,2,1) - digit-sum(200).
%o A241897 (PARI)
%o A241897 seq(maxp)={my(p=1,L=List(),s=0,k=0); while(p<maxp, p=nextprime(p+1); if(p==s-vecsum(digits(k,3)), listput(L,p)); k++; s+=vecsum(digits(p,3)));Vec(L)}
%o A241897 seq(1e7) \\ _Andrew Howroyd_, Mar 01 2018
%Y A241897 A240886. Primes p equal to the digit-sum in base 3 of all primes < p. A168161. Primes p which are equal to the sum of the binary digits in all primes <= p.
%K A241897 nonn,base
%O A241897 1,1
%A A241897 _Anthony Sand_, May 01 2014
%E A241897 a(29)-a(33) from _Andrew Howroyd_, Mar 02 2018