login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A026455 a(n) = least positive integer < a(n-1) and not a(i)*a(j)-2 for 1<=i<j<=n. 2
2, 3, 5, 6, 7, 9, 11, 14, 15, 17, 18, 21, 22, 23, 24, 27, 29, 30, 35, 36, 37, 38, 39, 41, 45, 47, 48, 50, 51, 54, 55, 57, 59, 60, 62, 63, 65, 66, 69, 71, 77, 78, 81, 84, 86, 87, 89, 90, 91, 93, 95, 99, 101, 102, 104, 105, 107, 110, 111, 114 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..1000

MATHEMATICA

a = {2, 3}; used = {a[[1]]*a[[2]] - 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; used = Union[used, k*a - 2]; AppendTo[a, k], {n, 3, 60}]; a (* Ivan Neretin, Mar 06 2016 *)

CROSSREFS

Cf. A026453 and references therein.

Sequence in context: A023884 A135607 A026453 * A082984 A085717 A253083

Adjacent sequences:  A026452 A026453 A026454 * A026456 A026457 A026458

KEYWORD

nonn

AUTHOR

Clark Kimberling

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 September 23 18:59 EDT 2021. Contains 347617 sequences. (Running on oeis4.)