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 A136627 #10 Jul 04 2020 03:12:09 %S A136627 4,3,4,3,3,3,3,3,3,2,4,5,4,2,2,2,3,3,4,3,3,2,3,2,1,0,2,3,4,3,3,3,3,1, %T A136627 2,2,3,3,3,2,3,3,3,1,1,2,3,2,1,1,1,1,2,2,3,2,2,2,2,2,2,2,2,1,3,3,3,1, %U A136627 2,3,5,4,4,3,2,0,1,2,2,1,1,1,1,1,2,2,2,1,2,2,1,0,2,2,4,3,3,1,0,1,1,2 %N A136627 For every number n in Ulam's spiral the sequence gives the number of primes around it (number n included). %C A136627 In Ulam's lattice there are 8 numbers around any number. The sequence is similar to A136626 with an increment of 1 for any prime position. %e A136627 Numbers around 13 are 3, 12, 29, 30, 31, 32, 33, 14 -> 3, 29, 31 and 13 itself are primes, so a(13)=4. %Y A136627 Cf. A063826, A115258, A136626. %K A136627 easy,nonn %O A136627 1,1 %A A136627 _Paolo P. Lava_ and _Giorgio Balzarotti_, Jan 14 2008 %E A136627 Offset 1 per example and correction for a(32) by _Kevin Ryde_, Jul 04 2020