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 A242385 #13 Mar 05 2022 14:18:36 %S A242385 13,97,113,193,283,397,479,673,953,1439,1597,2297,2699,3469,4219,4483, %T A242385 5323,7219,8273,9209,9403,10799,12097,13219,14879,15373,15619,21313, %U A242385 23399,26237,27883,32029,32749,34217,37243,39989,41203,42433,43669,46219,55219,60509,62497 %N A242385 Lesser of consecutive primes whose average is of the form k*(k+2), for some integer k. %e A242385 193 is in the sequence because 193 is prime, nextprime(193) = 197, and (193+197)/2 = 195 = 13*(13+2). %t A242385 Select[Partition[Prime[Range[6500]],2,1],IntegerQ[SolveValues[(k(k+2)) == Mean[#],k][[2]]]&][[All,1]] (* _Harvey P. Dale_, Mar 05 2022 *) %o A242385 (PARI) {k=2;while(k<10^5,l=nextprime(k+1);if(issquare((k+l)/2+1),print1(k,", "));k=l)} %Y A242385 Cf. A242384. %K A242385 nonn %O A242385 1,1 %A A242385 _Antonio Roldán_, May 12 2014