A382787 The product of exponents in the prime factorization of the numbers whose prime factorization contains exponents that are either 1 or even.
1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 4, 1, 2, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 4, 2, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 2, 6, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 4, 4, 1, 1, 2, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1
Offset: 1
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
Programs
-
Mathematica
f[n_] := Module[{e = FactorInteger[n][[;; , 2]]}, If[AllTrue[e, # == 1 || EvenQ[#] &], Times @@ e, Nothing]]; Array[f, 150] -
PARI
list(lim) = {my(e, ok); for(k = 1, lim, e = factor(k)[, 2]; ok = 1; for(i = 1, #e, if(e[i] > 1 && e[i]%2, ok = 0; break)); if(ok, print1(vecprod(e), ", ")));}
Comments