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!)
A251549 a(n) = smallest odd number not in {A098550(1), A098550(2), ..., A098550(n)}. 6
3, 3, 5, 5, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 11, 11, 11, 11, 11, 11, 11, 13, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 23, 23, 23, 23, 23, 23, 23, 23, 29, 29, 29, 29, 29, 29, 29, 29, 29 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A251416(n) = Min{A251546(n), a(n)}. - Reinhard Zumkeller, Dec 19 2014

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

MATHEMATICA

terms = 100;

f[lst_List] := Block[{k=4}, While[GCD[lst[[-2]], k] == 1 || GCD[lst[[-1]], k] > 1 || MemberQ[lst, k], k++]; Append[lst, k]];

A098550 = Nest[f, {1, 2, 3}, terms-3];

a[1] = 3;

a[n_] := a[n] = For[k = a[n-1], True, k = k+2, If[FreeQ[A098550[[1 ;; n]], k], Return[k]]];

Array[a, terms] (* Jean-Fran├žois Alcover, Aug 02 2018, after Robert G. Wilson v *)

PROG

(Haskell)

import Data.List ((\\))

a251549 n = head $ [1, 3 ..] \\ filter odd (take n a098550_list)

-- Reinhard Zumkeller, Dec 19 2014

CROSSREFS

Cf. A098550, A247253, A251416, A251417, A251546-A251552.

Sequence in context: A238371 A133772 A265182 * A129972 A130829 A196386

Adjacent sequences:  A251546 A251547 A251548 * A251550 A251551 A251552

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 18 2014

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 February 27 06:33 EST 2020. Contains 332299 sequences. (Running on oeis4.)