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 A173401 #7 Feb 06 2019 02:20:22
%S A173401 1,3,4,8,11,21,29,44,53,58,61,84,105,121,149,153,179,183,213,295,308,
%T A173401 374,461,502,535,552,609,637,659,727,730,756,850,859,865,875,885,914,
%U A173401 1005,1055,1105,1239,1261,1306,1321,1407,1443,1616,1654,1769,1783,1795,1836
%N A173401 Numbers k such that A075526(k-1) = A054546(k).
%p A173401 A008578 := proc(n) if n =1 then 1; else ithprime(n-1) ; end if; end proc:
%p A173401 A075526 := proc(n) A008578(n+2)-A008578(n+1) ; end proc:
%p A173401 A054546 := proc(n) if n <= 2 then op(n,[1,3]) ; else A002808(n-1)-A002808(n-2) ; end if; end proc:
%p A173401 for n from 1 to 2000 do if A075526(n-1) = A054546(n) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Apr 24 2010
%Y A173401 Cf. A054546, A075526, A173390, A173400.
%K A173401 nonn,less
%O A173401 1,2
%A A173401 _Juri-Stepan Gerasimov_, Feb 17 2010
%E A173401 Formula index corrected, a(14) corrected and sequence extended beyond a(14) by _R. J. Mathar_, Apr 25 2010