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 A067796 #16 Apr 24 2022 02:30:34 %S A067796 14,20,44,140,254,272,284,344,464,764,1224,1424,2064,3200,3824,11648, %T A067796 21584,25520,27644,38840,116544,235584,603584,632400,1677024,1935344, %U A067796 2049984,3763184,18460224,74649584,82448384,86648000,97507584,363939824,646139264,4294967294 %N A067796 Numbers k such that phi(k) + phi(k+1) = k. %t A067796 Select[Range[10^6], EulerPhi[#] + EulerPhi[# + 1] == # &] (* _Amiram Eldar_, Apr 23 2022 *) %Y A067796 Cf. A000010, A092404. %K A067796 nonn %O A067796 1,1 %A A067796 _Benoit Cloitre_, Feb 07 2002 %E A067796 a(22)-a(33) from _Donovan Johnson_, Mar 24 2011 %E A067796 a(34)-a(36) from _Amiram Eldar_, Apr 23 2022