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A028374
Numbers that have only curved digits {0, 3, 6, 8, 9} or digits that are both curved and linear {2, 5}.
11
0, 2, 3, 5, 6, 8, 9, 20, 22, 23, 25, 26, 28, 29, 30, 32, 33, 35, 36, 38, 39, 50, 52, 53, 55, 56, 58, 59, 60, 62, 63, 65, 66, 68, 69, 80, 82, 83, 85, 86, 88, 89, 90, 92, 93, 95, 96, 98, 99, 200, 202, 203, 205, 206, 208, 209, 220, 222, 223, 225, 226, 228, 229, 230, 232, 233
OFFSET
1,2
COMMENTS
From Bernard Schott, Mar 26 2023: (Start)
Previous name was: "Curved numbers: numbers that have only curved digits (0, 2, 3, 5, 6, 8, 9)"; but in fact, the curved numbers form the sequence A072960.
This sequence allows all digits except for 1, 4 and 7. (End)
EXAMPLE
From K. D. Bajpai, Sep 07 2014: (Start)
206 is in the sequence because it has only curved digits 2, 0 and 6.
208 is in the sequence because it has only curved digits 2, 0 and 8.
2035689 is the smallest number having all the curved digits.
(End)
MAPLE
N:= 3: S:= {0, 2, 3, 5, 6, 8, 9}: K:= S:
for j from 2 to N do
K:= map(t -> seq(10*t+s, s=S), K);
od:
print( K); # K. D. Bajpai, Sep 07 2014
MATHEMATICA
f[n_] := Block[{id = IntegerDigits[n], curve = {0, 2, 3, 5, 6, 8, 9}}, If[ Union[ Join[id, curve]] == curve, True, False]]; Select[ Range[0, 240], f[ # ] & ]
Select[Range[0, 249], Union[DigitCount[#] * {1, 0, 0, 1, 0, 0, 1, 0, 0, 0}] == {0} &] (* Alonso del Arte, May 23 2014 *)
Select[Range[0, 500], Intersection[IntegerDigits[#], {1, 4, 7}]=={}&] (* K. D. Bajpai, Sep 07 2014 *)
PROG
(Python)
for n in range(10**3):
s = str(n)
if not (s.count('1') + s.count('4') + s.count('7')):
print(n, end=', ') # Derek Orr, Sep 19 2014
(Magma) [n: n in [0..300] | Set(Intseq(n)) subset [0, 2, 3, 5, 6, 8, 9] ]; // Vincenzo Librandi, Sep 19 2014
CROSSREFS
Cf. A028373 (straight digits: 1, 4, 7), A072960 (curved digits: 0, 3, 6, 8, 9), A072961 (both straight and curved digits: 2, 5).
Combinations: A082741 (digits: 1, 2, 4, 5, 7), A361780 (digits: 0, 1, 3, 4, 6, 7, 8, 9).
Cf. A034470 (subsequence of primes).
Sequence in context: A335658 A364807 A294941 * A050578 A283513 A028776
KEYWORD
base,easy,nonn
AUTHOR
Greg Heil (gheil(AT)scn.org), Dec 11 1999
EXTENSIONS
Corrected and extended by Rick L. Shepherd, May 21 2003
Offset corrected by Arkadiusz Wesolowski, Aug 15 2011
Definition clarified by Bernard Schott, Mar 25 2023
STATUS
approved