VOOZH about

URL: https://oeis.org/history?seq=A242793

⇱ The On-Line Encyclopedia of Integer Sequences (OEIS)

login

Showing entries 1-10 | older changes
The minimal integer x such that each of the six integers x, x+1, x+2, x+4, x+5, x+6 is squarefree with exactly n prime divisors.
#20 by N. J. A. Sloane at Sat Jan 19 04:14:59 EST 2019
COMMENTS
CROSSREFS
Discussion
Sat Jan 19
04:14
OEIS Server: https://oeis.org/edit/global/2798
#19 by Alois P. Heinz at Sun Jun 01 15:03:53 EDT 2014
STATUS
#18 by Alois P. Heinz at Sun Jun 01 15:03:46 EDT 2014
NAME
EXAMPLE
STATUS
#17 by Ralf Stephan at Sat May 24 12:12:07 EDT 2014
STATUS
#16 by Joerg Arndt at Sat May 24 06:09:16 EDT 2014
STATUS
#15 by Joerg Arndt at Sat May 24 06:06:38 EDT 2014
KEYWORD
STATUS
#14 by Daniel Constantin Mayer at Fri May 23 15:08:17 EDT 2014
STATUS
Discussion
Sat May 24
00:23
Michel Marcus: You could prepend 7 for n=1 and change offset to 1.
It has exactly 1 prime divisor and verifies the squarefree condition.
Since it is equal to A068088 (1) + 3.
01:21
Tom Edgar: Michel, I think he means that all of the listed integers are square free with n divisors. Thus 7,8,9,11,12,13 wouldn't work. I think n=1 won't work because if x is square free and prime then x+1 will either be nonsquarefree or will have more than one prime divisor.
02:59
Michel Marcus: Oh yes, you're right. My mistake. Big mistake.
#13 by Daniel Constantin Mayer at Fri May 23 15:07:09 EDT 2014
PROG
STATUS
Discussion
Fri May 23
15:08
Daniel Constantin Mayer: Same updates in PROG as in A242804, A242805, A242806, A242829.
#12 by Daniel Constantin Mayer at Fri May 23 11:56:18 EDT 2014
STATUS
#11 by Daniel Constantin Mayer at Fri May 23 11:48:20 EDT 2014
DATA
COMMENTS
EXAMPLE
CROSSREFS
STATUS
Discussion
Fri May 23
11:54
Daniel Constantin Mayer: I regret that I had given the second term 8628052209 of the sequence A242829 originally, instead of the first term 6639266409, since the particularly hard sequence A242829 was computed in parallel processes by several machines, and the output for the interval from 6*10^9 to 7*10^9 was inadvertently overlooked in the primary evaluation.