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

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A138206 a(n) is the first term in a chain of at least n consecutive numbers each with exactly 6 distinct prime factors. 4
30030, 11243154, 323567034, 7933641735, 45212320502, 626804494291, 7563009743844 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(8) > 10^13. [Donovan Johnson, Jan 15 2009]

LINKS

Table of n, a(n) for n=1..7.

Roger B. Eggleton and James A. MacDougall, Consecutive integers with equally many principal divisors, Math. Mag. 81 (2008), 235-248. [T. D. Noe, Oct 13 2008]

CROSSREFS

Cf. A087977, A087978, A138207.

Cf. A154573. [Donovan Johnson, Jan 15 2009]

Sequence in context: A072940 A147573 A046324 * A031853 A066576 A104877

Adjacent sequences:  A138203 A138204 A138205 * A138207 A138208 A138209

KEYWORD

nonn,more

AUTHOR

Donovan Johnson, Mar 06 2008

EXTENSIONS

a(6)-a(7) from Donovan Johnson, Jan 15 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 16 15:31 EST 2019. Contains 319195 sequences. (Running on oeis4.)