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 A086291 #8 Jan 06 2020 08:36:19 %S A086291 0,1,1,2,1,1,1,3,2,1,2,1,1,4,2,2,1,3,2,3,2,1,5,1,2,3,1,2,4,2,2,3,3,2, %T A086291 2,6,1,3,2,4,4,2,2,5,2,2,1,3,4,3,3,2,7,3,2,4,2,2,5,4,3,2,2,3,6,2,3,1, %U A086291 3,5,2,4,5,2,3,2,8,3,3,5,2,2,2,6,4,4,3,2,3,3,3,7,3,4,4,2,4,2,6,2 %N A086291 Maximal exponent in prime factorization of 7-smooth numbers. %H A086291 Amiram Eldar, <a href="/A086291/b086291.txt">Table of n, a(n) for n = 1..10000</a> %F A086291 a(n) = A051903(A002473(n)). %F A086291 A086290(n) <= a(n) <= A086289(n). %t A086291 maxExp[1] = 0; maxExp[n_] := Max @@ Last /@ FactorInteger[n]; maxExp/@Select[Range[500], Max[Transpose[FactorInteger[#]][[1]]] <= 7 &] (* _Amiram Eldar_, Jan 06 2020 *) %Y A086291 Cf. A002473, A051903, A086289, A086290. %K A086291 nonn %O A086291 1,4 %A A086291 _Reinhard Zumkeller_, Jul 15 2003