OFFSET
1,1
REFERENCES
T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, page 2.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
L. Panaitopol, Some Properties of the Series of Composed Numbers, J. Inequalities in Pure and Applied Mathematics. 2(2): Article 38, 2000.
J. B. Rosser and L. Schoenfeld, Approximate formulas for some functions of prime numbers, Illinois J. Math. 6: 64-94 (1962).
Eric Weisstein's World of Mathematics, Composite Number.
Eric Weisstein's World of Mathematics, Prime Number.
MATHEMATICA
Module[{nn=20, cm, pr, len}, cm=Select[Range[nn], CompositeQ]; len = Length[ cm]; Table[#[[1]], #[[2]]]&/@Thread[{Prime[Range[len]], cm}]]//Flatten (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 06 2018 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Aug 12 2005
STATUS
approved