Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A019282
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A019282 Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,4)-perfect numbers. +0
1
15, 1023, 29127 (list; graph; listen)
OFFSET

1,1

COMMENT

See also the Cohen-te Reile links under A019276.

REFERENCES

Graeme L. Cohen and Herman J. J. te Riele, Iterating the sum-of-divisors function, Experimental Mathematics, 5 (1996), pp. 93-100.

LINKS

Experimental Mathematics, Home Page

CROSSREFS

Sequence in context: A055413 A067408 A102102 this_sequence A082158 A064625 A131313

Adjacent sequences: A019279 A019280 A019281 this_sequence A019283 A019284 A019285

KEYWORD

nonn,bref

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified December 2 11:54 EST 2009. Contains 167921 sequences.


AT&T Labs Research