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 A127925 #8 Jul 04 2025 10:04:58
%S A127925 3,7,19,23,43,47,73,109,113,199,283,293,313,317,463,467,503,509,523,
%T A127925 619,661,683,691,887,1063,1069,1109,1129,1303,1307,1321,1327,1613,
%U A127925 1621,1627,1637,1669,1789,2143,2161,2383,2393,2399,2477,2731,2753,2803,2861,2971
%N A127925 Primes p such that 2p < prime(k-i) + prime(k+i) for i=1..k-1, where p=prime(k).
%C A127925 One of several sets of "good primes" in section A14 of Guy.
%C A127925 McNew calls these numbers "midpoint convex primes". - _Peter Munn_, Jul 04 2025
%D A127925 R. K. Guy, Unsolved Problems in Number Theory, 3rd ed. Springer, 2004.
%H A127925 T. D. Noe, <a href="/A127925/b127925.txt">Table of n, a(n) for n=1..10001</a>
%H A127925 Nathan McNew, <a href="https://www.researchgate.net/profile/Nathan-Mcnew/publication/275363769_Popular_values_of_the_largest_prime_divisor_function/">Popular values of the largest prime divisor function</a> (corrected version), page 16, November 2015.
%t A127925 t={}; n=1; While[Length[t]<100, n++; p=Prime[n]; i=1; While[i<n && 2p<Prime[n-i]+Prime[n+i], i++ ]; If[i==n, AppendTo[t,p]]]; t
%Y A127925 Cf. A028388.
%Y A127925 A246033 is a subset.
%Y A127925 Subset of A124661, A178954.
%K A127925 nonn
%O A127925 1,1
%A A127925 _T. D. Noe_, Feb 06 2007