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A011537
Numbers that contain at least one 7.
30
7, 17, 27, 37, 47, 57, 67, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 87, 97, 107, 117, 127, 137, 147, 157, 167, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 187, 197, 207, 217, 227, 237, 247, 257, 267, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 287
OFFSET
1,1
COMMENTS
Subsequence of primes is A257668. - Bernard Schott, Jul 21 2021
FORMULA
a(n) ~ n. - Charles R Greathouse IV, Feb 12 2017
MATHEMATICA
Select[Range[300], DigitCount[#, 10, 7]>0&] (* Harvey P. Dale, Mar 29 2016 *)
PROG
(PARI) is(n)=!!setsearch(Set(digits(n)), 7) \\ Charles R Greathouse IV, Feb 12 2017
(GAP) Filtered([1..280], n->7 in ListOfDigits(n)); # Muniru A Asiru, Feb 23 2019
(Python)
def ok(n): return '7' in str(n)
print(list(filter(ok, range(290)))) # Michael S. Branicky, Jul 17 2021
CROSSREFS
Complement of A052419.
Cf. A257668.
Sequence in context: A354672 A261934 A253075 * A283610 A043517 A277594
KEYWORD
nonn,base,easy
STATUS
approved