login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A026448 a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for i<=1<=j<=n. 2
1, 2, 5, 8, 9, 13, 14, 17, 21, 22, 25, 26, 29, 32, 33, 37, 38, 41, 45, 48, 49, 53, 56, 57, 61, 62, 65, 69, 70, 73, 77, 80, 81, 85, 86, 89, 90, 93, 94, 97, 101, 102, 105, 109, 110, 113, 117, 118, 121, 122, 125, 129, 130, 133, 134, 137, 141 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
MATHEMATICA
a = {1, 2}; used = {a[[1]]^2 + 2, a[[1]]*a[[2]] + 2, a[[2]]^2 + 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; AppendTo[a, k]; used = Union[used, k*a + 2], {n, 3, 60}]; a (* Ivan Neretin, Mar 06 2016 *)
CROSSREFS
Cf. A026443 and references therein.
Sequence in context: A190768 A184866 A032684 * A258353 A173286 A243182
KEYWORD
nonn
AUTHOR
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 14 13:48 EDT 2024. Contains 371664 sequences. (Running on oeis4.)