A253443 Smallest missing number within the first n terms in A109890.

4, 4, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 34, 37, 37, 37, 37, 37

Offset

4,1

Comments

A253584(n) occurs exactly A253444(n) times.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 4..10000

Prog

(Haskell)
import Data.List (insert)
a253443 n = a253443_list !! (n-4)
a253443_list = f (4, []) 6 where
   f (m, ys) z = g $ dropWhile (< m) $ a027750_row' z where
     g (d:ds) | elem d ys = g ds
              | otherwise = m : f (ins [m, m+1 ..] (insert d ys)) (z + d)
     ins (u:us) vs'@(v:vs) = if u < v then (u, vs') else ins us vs
-- Reinhard Zumkeller, Jan 03 2015

Crossrefs

Cf. A095258, A095259, A253444 (run lengths), A253584 (range), A253415.

Sequence in context: A360997 A167770 A080800 * A140341 A332609 A244234

Adjacent sequences: A253440 A253441 A253442 * A253444 A253445 A253446

Keyword

nonn

Author

Reinhard Zumkeller, Jan 01 2015

Status

approved