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 A180724 #16 Apr 08 2023 16:35:59 %S A180724 7,16,29,48,67,96,125,160,197,234,283,336,389,448,507,572,641,720,797, %T A180724 880,963,1052,1147,1244,1349,1456,1557,1680,1787,1914,2045,2176,2309, %U A180724 2448,2587,2736,2883,3032,3197,3350,3523,3696,3869,4042,4229,4416,4601 %N A180724 a(n) = n^2 + largest prime < n^2. %H A180724 Harvey P. Dale, <a href="/A180724/b180724.txt">Table of n, a(n) for n = 2..1000</a> %F A180724 4 + 3 = 7; 9 + 7 = 16; 16 + 13 = 29; 25 + 23 = 48; %F A180724 a(n) = n^2+A053001(n). - _R. J. Mathar_, Sep 19 2010 %F A180724 2n^2 - O(n^1.05) < a(n) < 2n^2. (Probably a much tighter lower bound is true.) - _Charles R Greathouse IV_, Jan 31 2023 %t A180724 #+NextPrime[#,-1]&/@(Range[2,50]^2) (* _Harvey P. Dale_, Apr 08 2023 *) %o A180724 (PARI) a(n) = n^2 + precprime(n^2-1); \\ _Michel Marcus_, Aug 23 2013 %K A180724 nonn,easy %O A180724 2,1 %A A180724 _Ian Stewart_, Sep 18 2010