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 A358401 #17 Nov 21 2022 12:31:59 %S A358401 1,1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,-1,0,-1,-1,0,0,-1,-1,0,0,0,0,-1,-1, %T A358401 -1,-1,-1,-1,-1,0,-1,-1,-1,-1,-2,-1,-2,-2,-1,-1,-2,-1,-1,-1,-1,-1,-1, %U A358401 -1,-1,-1,0,0,-1,0,-1,-1,-1,0,0,0,0,0,0,0,-1,-1,-1,-1 %N A358401 Difference in number of 0's in first n terms of Van Eck's sequence and number of primes less than or equal to n. %F A358401 a(n) = A171896(n) - A000720(n). %e A358401 a(41) = -2 because there are 11 0's in the first 41 terms of Van Eck's sequence and 13 prime numbers less than or equal to 41, and 11 - 13 = -2. %Y A358401 Cf. A000040, A000720, A171896. %K A358401 sign %O A358401 1,41 %A A358401 _G. L. Honaker, Jr._, Nov 13 2022