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A011531 Numbers that contain a digit 1 in their decimal representation. 73
1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 31, 41, 51, 61, 71, 81, 91, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A121042(a(n)) = 1. - Reinhard Zumkeller, Jul 21 2006
See A043493 for numbers that contain a single digit '1'. A subsequence of numbers having a digit that divides all other digits, A263314. - M. F. Hasler, Jan 11 2016
LINKS
FORMULA
a(n) ~ n. - Charles R Greathouse IV, Nov 02 2022
MAPLE
M:= 3: # to get all terms of up to M digits
B:= {1}: A:= {1}:
for i from 2 to M do
B:= map(t -> seq(10*t+j, j=0..9), B) union
{seq(10*x+1, x=2*10^(i-2)..10^(i-1)-1)}:
A:= A union B;
od:
sort(convert(A, list)); # Robert Israel, Jan 10 2016
# second program:
A011531 := proc(n)
if n = 1 then
1;
else
for a from procname(n-1)+1 do
if nops(convert(convert(a, base, 10), set) intersect {1}) > 0 then
return a;
end if;
end do:
end if;
end proc: # R. J. Mathar, Jul 31 2016
MATHEMATICA
Select[Range[600] - 1, DigitCount[#, 10, 1] > 0 &] (* Vincenzo Librandi, Jan 11 2016 *)
PROG
(Haskell)
a011531 n = a011531_list !! (n-1)
a011531_list = filter ((elem '1') . show) [0..]
-- Reinhard Zumkeller, Feb 05 2012
(PARI) is_A011531(n)=setsearch(Set(digits(n)), 1) \\ M. F. Hasler, Jan 10 2016
(Magma) [n: n in [0..500] | 1 in Intseq(n) ]; // Vincenzo Librandi, Jan 11 2016
(GAP) Filtered([1..140], n->1 in ListOfDigits(n)); # Muniru A Asiru, Feb 23 2019
(Scala) (0 to 119).filter(_.toString.indexOf('1') > -1) // Alonso del Arte, Jan 12 2020
(Python)
def aupto(nn): return [m for m in range(1, nn+1) if '1' in str(m)]
print(aupto(133)) # Michael S. Branicky, Jan 10 2021
CROSSREFS
Cf. A052383 (complement), A062634 (a subsequence).
Sequence in context: A069715 A248499 A008716 * A257946 A070839 A161561
KEYWORD
nonn,base,easy
AUTHOR
STATUS
approved

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Last modified May 29 11:52 EDT 2024. Contains 372940 sequences. (Running on oeis4.)