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 A080066 #13 May 17 2025 22:43:28 %S A080066 6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,1,6,6,6,6, %T A080066 6,1,6,6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,1,6,6,6,6,6,1,6, %U A080066 6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,6,6,6,6,6,1,1,6,6,6,6,6,1,6,6,6,6,6,1,6 %N A080066 First differences of A000966 (number of zeros that n! will never end in). %C A080066 All terms in this sequence are either 1 or 6. - _Charles R Greathouse IV_, Jan 30 2023 %C A080066 The positions of 1 in this sequence are A000966, the sequence from which the differences were obtained. - _Paul C Abbott_, May 12 2025 %F A080066 a(n) = A000966(n+1) - A000966(n). %e A080066 E.g. A000966(5)=29, A000966(4)=23, so a(4)=29-23=6. %Y A080066 Cf. A000966. %Y A080066 Cf. A000142, A027868. %K A080066 base,nonn %O A080066 1,1 %A A080066 Mark Hudson (mrmarkhudson(AT)hotmail.com), Jan 24 2003 %E A080066 More terms from _Sascha Kurz_, Jan 27 2003