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A139819
Complement of repdigit numbers A010785.
7
10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 89
OFFSET
1,1
COMMENTS
Identical to (base 10) non-palindromic numbers A029742 up to a(83) = 101 which is a term of this sequence but not in A029742. - M. F. Hasler, Sep 08 2015
LINKS
Eric Weisstein's World of Mathematics, Repdigit.
Wikipedia, Repdigit
Chai Wah Wu, Algorithms for complementary sequences, arXiv:2409.05844 [math.NT], 2024.
FORMULA
A202022(a(n)) = 0. - Reinhard Zumkeller, Dec 09 2011
MAPLE
isA139819 := proc(n)
convert(n, base, 10) ;
convert(%, set) ;
simplify(nops(%) >1 ) ;
end proc: # R. J. Mathar, Jan 17 2017
PROG
(Haskell) a139819 n = a139819_list !! (n-1)
a139819_list = filter ((== 0) . a202022) [0..] -- Reinhard Zumkeller, Dec 09 2011
(PARI) is_A139819(n)=#Set(digits(n))>1 \\ M. F. Hasler, Sep 08 2015
(Python)
def A139819(n):
m, k = n, n+9*((l:=len(str(n)))-1)+9*n//(10**l-1)
while m != k:
m, k = k, n+9*((l:=len(str(k)))-1)+9*k//(10**l-1)
return m # Chai Wah Wu, Sep 04 2024
CROSSREFS
Cf. A066484 (subsequence).
Cf. A029742 (non-palindromic in base 10), A016038 (in any base), A050813 (in bases 2..10).
Sequence in context: A109394 A285687 A139704 * A288040 A031955 A029742
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Jun 02 2008
STATUS
approved

  NODES
Community 1
Intern 1
os 2
text 2
web 1