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A111655 n-th composite number appears n-th composite number times. 5


%S 4,4,4,4,6,6,6,6,6,6,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,10,10,10,10,10,

%T 10,10,10,10,10,12,12,12,12,12,12,12,12,12,12,12,12,14,14,14,14,14,14,

%U 14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15

%N n-th composite number appears n-th composite number times.

%D T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, page 2.

%D J. B. Rosser and L. Schoenfeld, Approximate formulas for some functions of prime numbers, Illinois J. Math. 6: 64-94 (1962).

%D L. Panaitopol, Some Properties of the Series of Composed [Composite] Numbers, J. Inequalities in Pure and Applied Mathematics. 2(2): Article 38, 2000.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CompositeNumber.html">Composite Number."</a>

%F A002808(n) appears A002808(n) times.

%Y Cf. A002808, A111653, A111654.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, Aug 12 2005

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Last modified January 26 13:09 EST 2022. Contains 350598 sequences. (Running on oeis4.)