A086291 - OEIS

%I #8 Jan 06 2020 08:36:19

%S 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 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 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 Maximal exponent in prime factorization of 7-smooth numbers.

%H Amiram Eldar, <a href="/A086291/b086291.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A051903(A002473(n)).

%F A086290(n) <= a(n) <= A086289(n).

%t maxExp[1] = 0; maxExp[n_] := Max @@ Last /@ FactorInteger[n]; maxExp/@Select[Range[500], Max[Transpose[FactorInteger[#]][[1]]] <= 7 &] (* _Amiram Eldar_, Jan 06 2020 *)

%Y Cf. A002473, A051903, A086289, A086290.

%K nonn

%O 1,4

%A _Reinhard Zumkeller_, Jul 15 2003