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 A137847 #10 Jun 04 2022 21:36:13
%S A137847 2,3,3,3,5,5,5,5,5,7,7,7,7,11,11,11,11,11,11,13,13,13,13,13,13,13,13,
%T A137847 17,17,17,17,17,19,19,19,19,23,23,23,23,23,23,29,29,29,29,29,29,29,29,
%U A137847 29,29,29,29,29,29,31,31,31,31,37,37,37,37,37,37,41,41,41,41,41,41,41,43
%N A137847 Smallest number missing in the EKG sequence (A064413) after n terms.
%C A137847 Lengths of runs gives A064425 prefixed by a 2.
%H A137847 <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%e A137847 a(1)=2 because the least integer absent in EKG with 1 term, {1}, is 2;
%e A137847 a(2..4)=3 because the least integer absent in EKG with 4 terms, {1,2,4,6}, is 3;
%e A137847 a(5..9)=5 because the least integer absent in EKG with 9 terms, {1,2,4,6,3,9,12,8,10}, is 5;
%e A137847 a(10..13)=7 because the least integer absent in EKG with 15 terms, {1,2,4,6,3,9,12,8,10}, is 7.
%Y A137847 Cf. A064413, A064425.
%K A137847 nonn
%O A137847 1,1
%A A137847 _Zak Seidov_, May 12 2008
%E A137847 Entries checked by _Jacques Tramu_ and _Vladeta Jovovic_.