OFFSET
1,4
COMMENTS
Introduced by Luis Flavio Soares Nunes - see link. Omega(n) <= a(n) for n > 1, where Omega(n) = the number of prime factors of n, counting multiplicity, A001222.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
Carlos Rivera, Puzzle #201 The Arithmetic Function A(n) in "The Prime Puzzles and Problems Connection".
FORMULA
MATHEMATICA
a[n_] := Module[{pf}, pf = Transpose[FactorInteger[n]]; Length[pf[[1]]]*Max[pf[[2]]]]; Table[a[i], {i, 2, 100}]
PROG
(PARI) a(n) = if(n == 1, 0, my(e = factor(n)[, 2]); vecmax(e) * #e); \\ Amiram Eldar, Sep 08 2024
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Joseph L. Pe, Nov 10 2002
EXTENSIONS
a(1)=0 prepended and more terms added by Antti Karttunen, May 28 2017
STATUS
approved