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 A072415 #11 Mar 13 2015 00:31:28
%S A072415 2,26,182,878,3626,13508,46922,155156,494468,1529590,4615074,13633310,
%T A072415 39548078,112918434,317920082,883996002
%N A072415 a(1) = 2; a(n) = a(n-1)-th even nontotient number.
%F A072415 a(3)=182 is the 26th = a(2)-th term in A005277.
%t A072415 a = Table[0, {10^6}]; Do[b = EulerPhi[n]/2; If[b < 10^6 + 1, a[[b]] = 1], {n, 1, 2 10^7}]; b = Select[ Range[10^6], a[[ # ]] == 0 &]; c = 1; Do[ Print[c]; c = 2b[[c]], {n, 0, 8}]
%Y A072415 Cf. A006508, A071255, A005277, A072416.
%K A072415 more,nonn
%O A072415 1,1
%A A072415 _Labos Elemer_, Jun 17 2002
%E A072415 Edited by _Robert G. Wilson v_, Jun 20 2002
%E A072415 a(11)-a(16) from _Donovan Johnson_, Oct 29 2010