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A256405
a(n) = smallest missing number after seeing A166133(n).
4
2, 3, 3, 5, 5, 5, 5, 9, 9, 9, 9, 13, 13, 13, 13, 17, 17, 17, 17, 17, 22, 22, 22, 25, 25, 25, 25, 25, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67
OFFSET
1,1
COMMENTS
The distinct terms are listed in A256408. See also A256409.
See the "blog" file in A166133 for discussion.
LINKS
John Mason, Table of n, a(n) for n = 1..722392 [10 megabytes]
John Mason, Table of n, a(n) for n = 1..2000000 [31 megabytes]
PROG
(Haskell)
import Data.List (delete); import Data.List.Ordered (isect)
a256405 n = a256405_list !! (n-1)
a256405_list = 2 : 3 : f (3:[5..]) 4 where
f zs@(z:_) x = z : f (delete y zs) y where
y = head $ isect (a027750_row' (x ^ 2 - 1)) zs
-- Reinhard Zumkeller, Apr 01 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 01 2015
STATUS
approved