login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A081810 If n = p_1^e_1 * ... * p_k^e_k, p_1 < ... < p_k primes, then a(n) = Max{ p_i*e_i }. 0
0, 2, 3, 4, 5, 3, 7, 6, 6, 5, 11, 4, 13, 7, 5, 8, 17, 6, 19, 5, 7, 11, 23, 6, 10, 13, 9, 7, 29, 5, 31, 10, 11, 17, 7, 6, 37, 19, 13, 6, 41, 7, 43, 11, 6, 23, 47, 8, 14, 10, 17, 13, 53, 9, 11, 7, 19, 29, 59, 5, 61, 31, 7, 12, 13, 11, 67, 17, 23, 7, 71, 6, 73, 37, 10, 19, 11, 13, 79, 8, 12 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

PROG

(PARI) a(n)=local(f); if(n<1, 0, f=factor(n); vecmax(vector(matsize(f)[1], k, f[k, 1]*f[k, 2])))

CROSSREFS

Sequence in context: A141295 A134198 A060653 * A071829 A067620 A053585

Adjacent sequences:  A081807 A081808 A081809 * A081811 A081812 A081813

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 10 2003

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 17:48 EST 2012. Contains 205939 sequences.