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URL: https://oeis.org/A375011

⇱ A375011 - OEIS

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A375011
a(n) = A373738(n) - A008479(n).
1
0, 1, 1, 1, 1, 3, 1, 1, 1, 4, 1, 5, 1, 4, 3, 1, 1, 6, 1, 5, 3, 5, 1, 6, 1, 5, 1, 5, 1, 11, 1, 1, 4, 5, 3, 8, 1, 5, 4, 7, 1, 12, 1, 6, 5, 6, 1, 8, 1, 7, 4, 6, 1, 8, 3, 7, 4, 6, 1, 17, 1, 6, 5, 1, 3, 14, 1, 6, 4, 12, 1, 9, 1, 6, 6, 6, 3, 15, 1, 8, 1, 7, 1, 18, 3
OFFSET
1,6
LINKS
Michael De Vlieger, Log log scatterplot of a(n), n = 2..2^20, ignoring a(1) = 0, with a color code where red indicates omega(n) = 2, gold omega(n) = 3, lime green = omega(n) = 4, spring green = omega(n) = 5, and blue = omega(n) = 6, where omega = A001221.
FORMULA
a(1) = 0; a(k) = 1 for k in A246655.
MATHEMATICA
{0}~Join~Table[facs = FactorInteger[n][[All, 1]]; r = Times @@ facs;
Floor[(1/PrimeNu[n]!)*Times @@ Map[Log[#, n] + 1 &, facs]] -
Count[Range[n], _?(Times @@ FactorInteger[#][[All, 1]] == r &)], {n, 2, 120}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Aug 14 2024
STATUS
approved