OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
Paul Erdős, Carl Pomerance, and Eric Schmutz, Carmichael's lambda function, Acta Arithmetica, Vol. 58, No. 4 (1991), pp. 363-385; alternative link.
FORMULA
a(n) = Sum_{k=1..n} A002322(k).
a(n) = (n^2/log(n)) * exp(B * (log(log(n))/log(log(log(n)))) * (1 + o(1))), where B = A218342 (Erdős et al., 1991). - Amiram Eldar, Dec 27 2022
MAPLE
read("transforms3") ; a002322 := BFILETOLIST("b002322.txt") : A162578 :=proc(n) global a002322 ; local i; add(op(i, a002322), i=1..n) ; end: seq(A162578(n), n=1..120) ; # R. J. Mathar, Jul 16 2009
MATHEMATICA
Accumulate[CarmichaelLambda[Range[60]]] (* Harvey P. Dale, Sep 21 2011 *)
PROG
(PARI) a(n) = sum(i=1, n, lcm(znstar(i)[2])) \\ Felix Fröhlich, Jul 04 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Jul 06 2009
EXTENSIONS
a(13) corrected and more terms added by R. J. Mathar, Jul 16 2009
STATUS
approved