|
|
A110194
|
|
First differences of A110095 (least nonprime sequence whose first differences are nonprime).
|
|
0
|
|
|
1, 8, 1, 4, 1, 1, 4, 1, 1, 4, 1, 1, 4, 1, 1, 1, 1, 4, 4, 1, 1, 4, 1, 1, 4, 1, 1, 4, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 4, 4, 1, 1, 4, 1, 1, 1, 1, 4, 4
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Conjecture: from a(5) on, are there only substrings <1 1 4> and <1 1 1 1 4 4 >?
|
|
LINKS
|
Table of n, a(n) for n=1..49.
|
|
EXAMPLE
|
Beginning with 1, we have to add 8 in order to get the first nonprime number (all other numbers <8 are prime or giving a prime). So 1+8=9 for a(2).
Then add 1=10 for a(3).
Then add (not 1 because 11 is prime; nor 2 and 3 because they are prime) ...add 4=14 for a(4), etc.
|
|
CROSSREFS
|
Cf. A110095 and twin-primes related sequences.
Sequence in context: A011469 A140457 A176457 * A199283 A079359 A010156
Adjacent sequences: A110191 A110192 A110193 * A110195 A110196 A110197
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Alexandre Wajnberg & Eric Angelini, Sep 06 2005
|
|
STATUS
|
approved
|
|
|
|