This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A329225 #10 Jun 26 2025 12:08:15
%S A329225 732722,23338590792,102091236,1,3,314,1,5,1,128,1,5,1,16,1,7,3,3,38,1,
%T A329225 1,1,5,1,1,9,1,9,3,1,1,3,1,5,11,1,7,1760,1,15,3,3,1,1,15,1,17,1,5,3,1,
%U A329225 1,1,3,1,1,15,1,9,1,25,70,27,1,1,19,35,1,19,3,1,1,1,7,41,1,5
%N A329225 a(n) is the smallest number k such that Sum_{i=1..k} Kronecker(prime(i),prime(n)) > 0 (or equivalently, Sum_{i=1..k} Kronecker(prime(i),prime(n)) = 1), or 0 if no such k exists.
%C A329225 a(n) is the index in primes of A329224(n), or 0 if A329224(n) = 0.
%C A329225 For further information see A329224, which is the main entry for these sequences.
%e A329225 For prime(10) = 29, k = 128 is the first case such that Sum_{i=1..k} Kronecker(prime(i),29) = 1 > 0, so a(10) = 128.
%o A329225 (PARI) a(n) = if(n==2, 23338590792, if(n==3, 102091236, my(p=prime(n), i=0); forprime(q=2, oo, i+=kronecker(q, p); if(i>0, return(primepi(q))))))
%Y A329225 Cf. A306502, A306503. See A329224 for the actual primes.
%K A329225 nonn
%O A329225 1,1
%A A329225 _Jianing Song_, Nov 08 2019
%E A329225 Edited by _Peter Munn_, Jun 26 2025