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 A206280 #9 Jun 28 2024 03:13:47 %S A206280 5,73,137,433,569,1217,5171,15859,16631,32027,35677,37619,39191,45767, %T A206280 59029,63997,65011,77813,92401,103669,186601,196201,230387,237161, %U A206280 261089,273517,439559,463747,484397,488573,505511,514079,519803,538739,544627,633599 %N A206280 Smallest of four consecutive primes whose sum is a square. %H A206280 Amiram Eldar, <a href="/A206280/b206280.txt">Table of n, a(n) for n = 1..10000</a> %F A206280 a(n) = A000040(A072849(n)). - _Amiram Eldar_, Jun 28 2024 %e A206280 a(4) = 433. The next three primes are 439, 443, and 449, and the sum of those four primes = 1764 = 42^2. %t A206280 Transpose[Select[Partition[Prime[Range[80000]],4,1],IntegerQ[Sqrt[ Total[#]]]&]][[1]] %Y A206280 Cf. A000040, A061275, A072849, A206279, A206281. %K A206280 nonn,easy %O A206280 1,1 %A A206280 _Harvey P. Dale_, Feb 05 2012